Google Git
Sign in
gnu / gcc / 82b61df521d17a96f60e56ede06a55a8894b1c2e / . / gcc / cp / typeck.c
blob: 05c0711ec14eb7984c3c6761f8e967e9afe06298 [file] [log] [blame]
/* Build expressions with type checking for C++ compiler.
Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
1999, 2000, 2001 Free Software Foundation, Inc.
Hacked by Michael Tiemann (tiemann@cygnus.com)
This file is part of GNU CC.
GNU CC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU CC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING. If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
/* This file is part of the C++ front end.
It contains routines to build C++ expressions given their operands,
including computing the types of the result, C and C++ specific error
checks, and some optimization.
There are also routines to build RETURN_STMT nodes and CASE_STMT nodes,
and to process initializations in declarations (since they work
like a strange sort of assignment). */
#include "config.h"
#include "system.h"
#include "tree.h"
#include "rtl.h"
#include "expr.h"
#include "cp-tree.h"
#include "tm_p.h"
#include "flags.h"
#include "output.h"
#include "toplev.h"
#include "diagnostic.h"
#include "target.h"
static tree convert_for_assignment PARAMS ((tree, tree, const char *, tree,
int));
static tree pointer_int_sum PARAMS ((enum tree_code, tree, tree));
static tree rationalize_conditional_expr PARAMS ((enum tree_code, tree));
static int comp_target_parms PARAMS ((tree, tree));
static int comp_ptr_ttypes_real PARAMS ((tree, tree, int));
static int comp_ptr_ttypes_const PARAMS ((tree, tree));
static int comp_ptr_ttypes_reinterpret PARAMS ((tree, tree));
static int comp_except_types PARAMS ((tree, tree, int));
static int comp_array_types PARAMS ((int (*) (tree, tree, int), tree,
tree, int));
static tree common_base_type PARAMS ((tree, tree));
static tree lookup_anon_field PARAMS ((tree, tree));
static tree pointer_diff PARAMS ((tree, tree, tree));
static tree build_component_addr PARAMS ((tree, tree));
static tree qualify_type_recursive PARAMS ((tree, tree));
static tree get_delta_difference PARAMS ((tree, tree, int));
static int comp_cv_target_types PARAMS ((tree, tree, int));
static void casts_away_constness_r PARAMS ((tree *, tree *));
static int casts_away_constness PARAMS ((tree, tree));
static void maybe_warn_about_returning_address_of_local PARAMS ((tree));
static tree strip_all_pointer_quals PARAMS ((tree));
/* Return the target type of TYPE, which means return T for:
T*, T&, T[], T (...), and otherwise, just T. */
tree
target_type (type)
tree type;
{
if (TREE_CODE (type) == REFERENCE_TYPE)
type = TREE_TYPE (type);
while (TREE_CODE (type) == POINTER_TYPE
|| TREE_CODE (type) == ARRAY_TYPE
|| TREE_CODE (type) == FUNCTION_TYPE
|| TREE_CODE (type) == METHOD_TYPE
|| TREE_CODE (type) == OFFSET_TYPE)
type = TREE_TYPE (type);
return type;
}
/* Do `exp = require_complete_type (exp);' to make sure exp
does not have an incomplete type. (That includes void types.)
Returns the error_mark_node if the VALUE does not have
complete type when this function returns. */
tree
require_complete_type (value)
tree value;
{
tree type;
if (processing_template_decl || value == error_mark_node)
return value;
if (TREE_CODE (value) == OVERLOAD)
type = unknown_type_node;
else
type = TREE_TYPE (value);
/* First, detect a valid value with a complete type. */
if (COMPLETE_TYPE_P (type))
return value;
/* If we see X::Y, we build an OFFSET_TYPE which has
not been laid out. Try to avoid an error by interpreting
it as this->X::Y, if reasonable. */
if (TREE_CODE (value) == OFFSET_REF
&& current_class_ref != 0
&& TREE_OPERAND (value, 0) == current_class_ref)
{
tree base, member = TREE_OPERAND (value, 1);
tree basetype = TYPE_OFFSET_BASETYPE (type);
my_friendly_assert (TREE_CODE (member) == FIELD_DECL, 305);
basetype = lookup_base (current_class_type, basetype, ba_check, NULL);
base = build_base_path (PLUS_EXPR, current_class_ptr, basetype, 1);
value = build (COMPONENT_REF, TREE_TYPE (member),
build_indirect_ref (base, NULL), member);
return require_complete_type (value);
}
if (complete_type_or_else (type, value))
return value;
else
return error_mark_node;
}
/* Try to complete TYPE, if it is incomplete. For example, if TYPE is
a template instantiation, do the instantiation. Returns TYPE,
whether or not it could be completed, unless something goes
horribly wrong, in which case the error_mark_node is returned. */
tree
complete_type (type)
tree type;
{
if (type == NULL_TREE)
/* Rather than crash, we return something sure to cause an error
at some point. */
return error_mark_node;
if (type == error_mark_node || COMPLETE_TYPE_P (type))
;
else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
{
tree t = complete_type (TREE_TYPE (type));
if (COMPLETE_TYPE_P (t) && ! processing_template_decl)
layout_type (type);
TYPE_NEEDS_CONSTRUCTING (type)
= TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t));
TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t));
}
else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
instantiate_class_template (TYPE_MAIN_VARIANT (type));
return type;
}
/* Like complete_type, but issue an error if the TYPE cannot be
completed. VALUE is used for informative diagnostics.
Returns NULL_TREE if the type cannot be made complete. */
tree
complete_type_or_else (type, value)
tree type;
tree value;
{
type = complete_type (type);
if (type == error_mark_node)
/* We already issued an error. */
return NULL_TREE;
else if (!COMPLETE_TYPE_P (type))
{
incomplete_type_error (value, type);
return NULL_TREE;
}
else
return type;
}
/* Return truthvalue of whether type of EXP is instantiated. */
int
type_unknown_p (exp)
tree exp;
{
return (TREE_CODE (exp) == OVERLOAD
|| TREE_CODE (exp) == TREE_LIST
|| TREE_TYPE (exp) == unknown_type_node
|| (TREE_CODE (TREE_TYPE (exp)) == OFFSET_TYPE
&& TREE_TYPE (TREE_TYPE (exp)) == unknown_type_node));
}
/* Return a pointer or pointer to member type similar to T1, with a
cv-qualification signature that is the union of the cv-qualification
signatures of T1 and T2: [expr.rel], [expr.eq]. */
static tree
qualify_type_recursive (t1, t2)
tree t1, t2;
{
if ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
|| (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2)))
{
tree tt1 = TREE_TYPE (t1);
tree tt2 = TREE_TYPE (t2);
tree b1;
int type_quals;
tree tgt;
tree attributes = (*targetm.merge_type_attributes) (t1, t2);
if (TREE_CODE (tt1) == OFFSET_TYPE)
{
b1 = TYPE_OFFSET_BASETYPE (tt1);
tt1 = TREE_TYPE (tt1);
tt2 = TREE_TYPE (tt2);
}
else
b1 = NULL_TREE;
type_quals = (cp_type_quals (tt1) | cp_type_quals (tt2));
tgt = qualify_type_recursive (tt1, tt2);
tgt = cp_build_qualified_type (tgt, type_quals);
if (b1)
tgt = build_offset_type (b1, tgt);
t1 = build_pointer_type (tgt);
t1 = build_type_attribute_variant (t1, attributes);
}
return t1;
}
/* Return the common type of two parameter lists.
We assume that comptypes has already been done and returned 1;
if that isn't so, this may crash.
As an optimization, free the space we allocate if the parameter
lists are already common. */
tree
commonparms (p1, p2)
tree p1, p2;
{
tree oldargs = p1, newargs, n;
int i, len;
int any_change = 0;
len = list_length (p1);
newargs = tree_last (p1);
if (newargs == void_list_node)
i = 1;
else
{
i = 0;
newargs = 0;
}
for (; i < len; i++)
newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
n = newargs;
for (i = 0; p1;
p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n), i++)
{
if (TREE_PURPOSE (p1) && !TREE_PURPOSE (p2))
{
TREE_PURPOSE (n) = TREE_PURPOSE (p1);
any_change = 1;
}
else if (! TREE_PURPOSE (p1))
{
if (TREE_PURPOSE (p2))
{
TREE_PURPOSE (n) = TREE_PURPOSE (p2);
any_change = 1;
}
}
else
{
if (1 != simple_cst_equal (TREE_PURPOSE (p1), TREE_PURPOSE (p2)))
any_change = 1;
TREE_PURPOSE (n) = TREE_PURPOSE (p2);
}
if (TREE_VALUE (p1) != TREE_VALUE (p2))
{
any_change = 1;
TREE_VALUE (n) = common_type (TREE_VALUE (p1), TREE_VALUE (p2));
}
else
TREE_VALUE (n) = TREE_VALUE (p1);
}
if (! any_change)
return oldargs;
return newargs;
}
/* Given a type, perhaps copied for a typedef,
find the "original" version of it. */
tree
original_type (t)
tree t;
{
while (TYPE_NAME (t) != NULL_TREE)
{
tree x = TYPE_NAME (t);
if (TREE_CODE (x) != TYPE_DECL)
break;
x = DECL_ORIGINAL_TYPE (x);
if (x == NULL_TREE)
break;
t = x;
}
return t;
}
/* T1 and T2 are arithmetic or enumeration types. Return the type
that will result from the "usual arithmetic conversions" on T1 and
T2 as described in [expr]. */
tree
type_after_usual_arithmetic_conversions (t1, t2)
tree t1;
tree t2;
{
enum tree_code code1 = TREE_CODE (t1);
enum tree_code code2 = TREE_CODE (t2);
tree attributes;
/* FIXME: Attributes. */
my_friendly_assert (ARITHMETIC_TYPE_P (t1)
|| TREE_CODE (t1) == ENUMERAL_TYPE,
19990725);
my_friendly_assert (ARITHMETIC_TYPE_P (t2)
|| TREE_CODE (t2) == ENUMERAL_TYPE,
19990725);
/* In what follows, we slightly generalize the rules given in [expr]
so as to deal with `long long'. First, merge the attributes. */
attributes = (*targetm.merge_type_attributes) (t1, t2);
/* If only one is real, use it as the result. */
if (code1 == REAL_TYPE && code2 != REAL_TYPE)
return build_type_attribute_variant (t1, attributes);
if (code2 == REAL_TYPE && code1 != REAL_TYPE)
return build_type_attribute_variant (t2, attributes);
/* Perform the integral promotions. */
if (code1 != REAL_TYPE)
{
t1 = type_promotes_to (t1);
t2 = type_promotes_to (t2);
}
/* Both real or both integers; use the one with greater precision. */
if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
return build_type_attribute_variant (t1, attributes);
else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
return build_type_attribute_variant (t2, attributes);
if (code1 != REAL_TYPE)
{
/* If one is a sizetype, use it so size_binop doesn't blow up. */
if (TYPE_IS_SIZETYPE (t1) > TYPE_IS_SIZETYPE (t2))
return build_type_attribute_variant (t1, attributes);
if (TYPE_IS_SIZETYPE (t2) > TYPE_IS_SIZETYPE (t1))
return build_type_attribute_variant (t2, attributes);
/* If one is unsigned long long, then convert the other to unsigned
long long. */
if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
|| same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
return build_type_attribute_variant (long_long_unsigned_type_node,
attributes);
/* If one is a long long, and the other is an unsigned long, and
long long can represent all the values of an unsigned long, then
convert to a long long. Otherwise, convert to an unsigned long
long. Otherwise, if either operand is long long, convert the
other to long long.
Since we're here, we know the TYPE_PRECISION is the same;
therefore converting to long long cannot represent all the values
of an unsigned long, so we choose unsigned long long in that
case. */
if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
|| same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
{
tree t = ((TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2))
? long_long_unsigned_type_node
: long_long_integer_type_node);
return build_type_attribute_variant (t, attributes);
}
/* Go through the same procedure, but for longs. */
if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
|| same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
return build_type_attribute_variant (long_unsigned_type_node,
attributes);
if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
|| same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
{
tree t = ((TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2))
? long_unsigned_type_node : long_integer_type_node);
return build_type_attribute_variant (t, attributes);
}
/* Otherwise prefer the unsigned one. */
if (TREE_UNSIGNED (t1))
return build_type_attribute_variant (t1, attributes);
else
return build_type_attribute_variant (t2, attributes);
}
else
{
if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
|| same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
return build_type_attribute_variant (long_double_type_node,
attributes);
if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
|| same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
return build_type_attribute_variant (double_type_node,
attributes);
else
return build_type_attribute_variant (float_type_node,
attributes);
}
}
/* Return the composite pointer type (see [expr.rel]) for T1 and T2.
ARG1 and ARG2 are the values with those types. The LOCATION is a
string describing the current location, in case an error occurs. */
tree
composite_pointer_type (t1, t2, arg1, arg2, location)
tree t1;
tree t2;
tree arg1;
tree arg2;
const char* location;
{
tree result_type;
/* [expr.rel]
If one operand is a null pointer constant, the composite pointer
type is the type of the other operand. */
if (null_ptr_cst_p (arg1))
return t2;
if (null_ptr_cst_p (arg2))
return t1;
/* Deal with pointer-to-member functions in the same way as we deal
with pointers to functions. */
if (TYPE_PTRMEMFUNC_P (t1))
t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
if (TYPE_PTRMEMFUNC_P (t2))
t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
/* We have:
[expr.rel]
If one of the operands has type "pointer to cv1 void*", then
the other has type "pointer to cv2T", and the composite pointer
type is "pointer to cv12 void", where cv12 is the union of cv1
and cv2.
If either type is a pointer to void, make sure it is T1. */
if (VOID_TYPE_P (TREE_TYPE (t2)))
{
tree t;
t = t1;
t1 = t2;
t2 = t;
}
/* Now, if T1 is a pointer to void, merge the qualifiers. */
if (VOID_TYPE_P (TREE_TYPE (t1)))
{
if (pedantic && TYPE_PTRFN_P (t2))
pedwarn ("ISO C++ forbids %s between pointer of type `void *' and pointer-to-function", location);
t1 = TREE_TYPE (t1);
t2 = TREE_TYPE (t2);
result_type = cp_build_qualified_type (void_type_node,
(cp_type_quals (t1)
| cp_type_quals (t2)));
result_type = build_pointer_type (result_type);
}
else
{
tree full1 = qualify_type_recursive (t1, t2);
tree full2 = qualify_type_recursive (t2, t1);
int val = comp_target_types (full1, full2, 1);
if (val > 0)
result_type = full1;
else if (val < 0)
result_type = full2;
else
{
pedwarn ("%s between distinct pointer types `%T' and `%T' lacks a cast",
location, t1, t2);
result_type = ptr_type_node;
}
}
return result_type;
}
/* Return the common type of two types.
We assume that comptypes has already been done and returned 1;
if that isn't so, this may crash.
This is the type for the result of most arithmetic operations
if the operands have the given two types.
We do not deal with enumeral types here because they have already been
converted to integer types. */
tree
common_type (t1, t2)
tree t1, t2;
{
register enum tree_code code1;
register enum tree_code code2;
tree attributes;
/* Save time if the two types are the same. */
if (t1 == t2)
return t1;
t1 = original_type (t1);
t2 = original_type (t2);
if (t1 == t2)
return t1;
/* If one type is nonsense, use the other. */
if (t1 == error_mark_node)
return t2;
if (t2 == error_mark_node)
return t1;
if ((ARITHMETIC_TYPE_P (t1) || TREE_CODE (t1) == ENUMERAL_TYPE)
&& (ARITHMETIC_TYPE_P (t2) || TREE_CODE (t2) == ENUMERAL_TYPE))
return type_after_usual_arithmetic_conversions (t1, t2);
/* Merge the attributes. */
attributes = (*targetm.merge_type_attributes) (t1, t2);
/* Treat an enum type as the unsigned integer type of the same width. */
if (TREE_CODE (t1) == ENUMERAL_TYPE)
t1 = type_for_size (TYPE_PRECISION (t1), 1);
if (TREE_CODE (t2) == ENUMERAL_TYPE)
t2 = type_for_size (TYPE_PRECISION (t2), 1);
if (TYPE_PTRMEMFUNC_P (t1))
t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
if (TYPE_PTRMEMFUNC_P (t2))
t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
code1 = TREE_CODE (t1);
code2 = TREE_CODE (t2);
/* If one type is complex, form the common type of the non-complex
components, then make that complex. Use T1 or T2 if it is the
required type. */
if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
{
tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
tree subtype = common_type (subtype1, subtype2);
if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
return build_type_attribute_variant (t1, attributes);
else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
return build_type_attribute_variant (t2, attributes);
else
return build_type_attribute_variant (build_complex_type (subtype),
attributes);
}
switch (code1)
{
case INTEGER_TYPE:
case REAL_TYPE:
/* We should have called type_after_usual_arithmetic_conversions
above. */
my_friendly_abort (19990725);
break;
case POINTER_TYPE:
case REFERENCE_TYPE:
/* For two pointers, do this recursively on the target type,
and combine the qualifiers of the two types' targets. */
/* This code was turned off; I don't know why.
But ISO C++ specifies doing this with the qualifiers.
So I turned it on again. */
{
tree tt1 = TREE_TYPE (t1);
tree tt2 = TREE_TYPE (t2);
tree b1, b2;
int type_quals;
tree target;
if (TREE_CODE (tt1) == OFFSET_TYPE)
{
b1 = TYPE_OFFSET_BASETYPE (tt1);
b2 = TYPE_OFFSET_BASETYPE (tt2);
tt1 = TREE_TYPE (tt1);
tt2 = TREE_TYPE (tt2);
}
else
b1 = b2 = NULL_TREE;
type_quals = (cp_type_quals (tt1) | cp_type_quals (tt2));
tt1 = TYPE_MAIN_VARIANT (tt1);
tt2 = TYPE_MAIN_VARIANT (tt2);
if (tt1 == tt2)
target = tt1;
else if (VOID_TYPE_P (tt1) || VOID_TYPE_P (tt2))
target = void_type_node;
else if (tt1 == unknown_type_node)
target = tt2;
else if (tt2 == unknown_type_node)
target = tt1;
else
target = common_type (tt1, tt2);
target = cp_build_qualified_type (target, type_quals);
if (b1)
{
if (same_type_p (b1, b2)
|| (DERIVED_FROM_P (b1, b2) && binfo_or_else (b1, b2)))
target = build_offset_type (b2, target);
else if (binfo_or_else (b2, b1))
target = build_offset_type (b1, target);
}
if (code1 == POINTER_TYPE)
t1 = build_pointer_type (target);
else
t1 = build_reference_type (target);
t1 = build_type_attribute_variant (t1, attributes);
if (TREE_CODE (target) == METHOD_TYPE)
t1 = build_ptrmemfunc_type (t1);
return t1;
}
case ARRAY_TYPE:
{
tree elt = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
/* Save space: see if the result is identical to one of the args. */
if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
return build_type_attribute_variant (t1, attributes);
if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
return build_type_attribute_variant (t2, attributes);
/* Merge the element types, and have a size if either arg has one. */
t1 = build_cplus_array_type
(elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
return build_type_attribute_variant (t1, attributes);
}
case FUNCTION_TYPE:
/* Function types: prefer the one that specified arg types.
If both do, merge the arg types. Also merge the return types. */
{
tree valtype = common_type (TREE_TYPE (t1), TREE_TYPE (t2));
tree p1 = TYPE_ARG_TYPES (t1);
tree p2 = TYPE_ARG_TYPES (t2);
tree rval, raises;
/* Save space: see if the result is identical to one of the args. */
if (valtype == TREE_TYPE (t1) && ! p2)
return build_type_attribute_variant (t1, attributes);
if (valtype == TREE_TYPE (t2) && ! p1)
return build_type_attribute_variant (t2, attributes);
/* Simple way if one arg fails to specify argument types. */
if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
{
rval = build_function_type (valtype, p2);
if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
rval = build_exception_variant (rval, raises);
return build_type_attribute_variant (rval, attributes);
}
raises = TYPE_RAISES_EXCEPTIONS (t1);
if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
{
rval = build_function_type (valtype, p1);
if (raises)
rval = build_exception_variant (rval, raises);
return build_type_attribute_variant (rval, attributes);
}
rval = build_function_type (valtype, commonparms (p1, p2));
rval = build_exception_variant (rval, raises);
return build_type_attribute_variant (rval, attributes);
}
case RECORD_TYPE:
case UNION_TYPE:
t1 = TYPE_MAIN_VARIANT (t1);
t2 = TYPE_MAIN_VARIANT (t2);
if (DERIVED_FROM_P (t1, t2) && binfo_or_else (t1, t2))
return build_type_attribute_variant (t1, attributes);
else if (binfo_or_else (t2, t1))
return build_type_attribute_variant (t2, attributes);
else
{
compiler_error ("common_type called with uncommon aggregate types");
return error_mark_node;
}
case METHOD_TYPE:
if (TREE_CODE (TREE_TYPE (t1)) == TREE_CODE (TREE_TYPE (t2)))
{
/* Get this value the long way, since TYPE_METHOD_BASETYPE
is just the main variant of this. */
tree basetype;
tree raises, t3;
tree b1 = TYPE_OFFSET_BASETYPE (t1);
tree b2 = TYPE_OFFSET_BASETYPE (t2);
if (same_type_p (b1, b2)
|| (DERIVED_FROM_P (b1, b2) && binfo_or_else (b1, b2)))
basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
else
{
if (binfo_or_else (b2, b1) == NULL_TREE)
compiler_error ("common_type called with uncommon method types");
basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t1)));
}
raises = TYPE_RAISES_EXCEPTIONS (t1);
/* If this was a member function type, get back to the
original type of type member function (i.e., without
the class instance variable up front. */
t1 = build_function_type (TREE_TYPE (t1),
TREE_CHAIN (TYPE_ARG_TYPES (t1)));
t2 = build_function_type (TREE_TYPE (t2),
TREE_CHAIN (TYPE_ARG_TYPES (t2)));
t3 = common_type (t1, t2);
t3 = build_cplus_method_type (basetype, TREE_TYPE (t3),
TYPE_ARG_TYPES (t3));
t1 = build_exception_variant (t3, raises);
}
else
compiler_error ("common_type called with uncommon method types");
return build_type_attribute_variant (t1, attributes);
case OFFSET_TYPE:
/* Pointers to members should now be handled by the POINTER_TYPE
case above. */
my_friendly_abort (990325);
default:
return build_type_attribute_variant (t1, attributes);
}
}
/* Compare two exception specifier types for exactness or subsetness, if
allowed. Returns 0 for mismatch, 1 for same, 2 if B is allowed by A.
[except.spec] "If a class X ... objects of class X or any class publicly
and unambigously derrived from X. Similarly, if a pointer type Y * ...
exceptions of type Y * or that are pointers to any type publicly and
unambigously derrived from Y. Otherwise a function only allows exceptions
that have the same type ..."
This does not mention cv qualifiers and is different to what throw
[except.throw] and catch [except.catch] will do. They will ignore the
top level cv qualifiers, and allow qualifiers in the pointer to class
example.
We implement the letter of the standard. */
static int
comp_except_types (a, b, exact)
tree a, b;
int exact;
{
if (same_type_p (a, b))
return 1;
else if (!exact)
{
if (cp_type_quals (a) || cp_type_quals (b))
return 0;
if (TREE_CODE (a) == POINTER_TYPE
&& TREE_CODE (b) == POINTER_TYPE)
{
a = TREE_TYPE (a);
b = TREE_TYPE (b);
if (cp_type_quals (a) || cp_type_quals (b))
return 0;
}
if (TREE_CODE (a) != RECORD_TYPE
|| TREE_CODE (b) != RECORD_TYPE)
return 0;
if (ACCESSIBLY_UNIQUELY_DERIVED_P (a, b))
return 2;
}
return 0;
}
/* Return 1 if TYPE1 and TYPE2 are equivalent exception specifiers.
If EXACT is 0, T2 can be a subset of T1 (according to 15.4/7),
otherwise it must be exact. Exception lists are unordered, but
we've already filtered out duplicates. Most lists will be in order,
we should try to make use of that. */
int
comp_except_specs (t1, t2, exact)
tree t1, t2;
int exact;
{
tree probe;
tree base;
int length = 0;
if (t1 == t2)
return 1;
if (t1 == NULL_TREE) /* T1 is ... */
return t2 == NULL_TREE || !exact;
if (!TREE_VALUE (t1)) /* t1 is EMPTY */
return t2 != NULL_TREE && !TREE_VALUE (t2);
if (t2 == NULL_TREE) /* T2 is ... */
return 0;
if (TREE_VALUE(t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
return !exact;
/* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
Count how many we find, to determine exactness. For exact matching and
ordered T1, T2, this is an O(n) operation, otherwise its worst case is
O(nm). */
for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
{
for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
{
tree a = TREE_VALUE (probe);
tree b = TREE_VALUE (t2);
if (comp_except_types (a, b, exact))
{
if (probe == base && exact)
base = TREE_CHAIN (probe);
length++;
break;
}
}
if (probe == NULL_TREE)
return 0;
}
return !exact || base == NULL_TREE || length == list_length (t1);
}
/* Compare the array types T1 and T2, using CMP as the type comparison
function for the element types. STRICT is as for comptypes. */
static int
comp_array_types (cmp, t1, t2, strict)
register int (*cmp) PARAMS ((tree, tree, int));
tree t1, t2;
int strict;
{
tree d1;
tree d2;
if (t1 == t2)
return 1;
/* The type of the array elements must be the same. */
if (!(TREE_TYPE (t1) == TREE_TYPE (t2)
|| (*cmp) (TREE_TYPE (t1), TREE_TYPE (t2),
strict & ~COMPARE_REDECLARATION)))
return 0;
d1 = TYPE_DOMAIN (t1);
d2 = TYPE_DOMAIN (t2);
if (d1 == d2)
return 1;
/* If one of the arrays is dimensionless, and the other has a
dimension, they are of different types. However, it is legal to
write:
extern int a[];
int a[3];
by [basic.link]:
declarations for an array object can specify
array types that differ by the presence or absence of a major
array bound (_dcl.array_). */
if (!d1 || !d2)
return strict & COMPARE_REDECLARATION;
/* Check that the dimensions are the same. */
return (cp_tree_equal (TYPE_MIN_VALUE (d1),
TYPE_MIN_VALUE (d2))
&& cp_tree_equal (TYPE_MAX_VALUE (d1),
TYPE_MAX_VALUE (d2)));
}
/* Return 1 if T1 and T2 are compatible types for assignment or
various other operations. STRICT is a bitwise-or of the COMPARE_*
flags. */
int
comptypes (t1, t2, strict)
tree t1;
tree t2;
int strict;
{
int attrval, val;
int orig_strict = strict;
/* The special exemption for redeclaring array types without an
array bound only applies at the top level:
extern int (*i)[];
int (*i)[8];
is not legal, for example. */
strict &= ~COMPARE_REDECLARATION;
/* Suppress errors caused by previously reported errors */
if (t1 == t2)
return 1;
/* This should never happen. */
my_friendly_assert (t1 != error_mark_node, 307);
if (t2 == error_mark_node)
return 0;
/* If either type is the internal version of sizetype, return the
language version. */
if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
&& TYPE_DOMAIN (t1) != 0)
t1 = TYPE_DOMAIN (t1);
if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
&& TYPE_DOMAIN (t2) != 0)
t2 = TYPE_DOMAIN (t2);
if (strict & COMPARE_RELAXED)
{
/* Treat an enum type as the unsigned integer type of the same width. */
if (TREE_CODE (t1) == ENUMERAL_TYPE)
t1 = type_for_size (TYPE_PRECISION (t1), 1);
if (TREE_CODE (t2) == ENUMERAL_TYPE)
t2 = type_for_size (TYPE_PRECISION (t2), 1);
if (t1 == t2)
return 1;
}
if (TYPE_PTRMEMFUNC_P (t1))
t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
if (TYPE_PTRMEMFUNC_P (t2))
t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
/* Different classes of types can't be compatible. */
if (TREE_CODE (t1) != TREE_CODE (t2))
return 0;
/* Qualifiers must match. */
if (cp_type_quals (t1) != cp_type_quals (t2))
return 0;
if (strict == COMPARE_STRICT
&& TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
return 0;
/* Allow for two different type nodes which have essentially the same
definition. Note that we already checked for equality of the type
qualifiers (just above). */
if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
return 1;
if (strict & COMPARE_NO_ATTRIBUTES)
attrval = 1;
/* 1 if no need for warning yet, 2 if warning cause has been seen. */
else if (! (attrval = (*targetm.comp_type_attributes) (t1, t2)))
return 0;
/* 1 if no need for warning yet, 2 if warning cause has been seen. */
val = 0;
switch (TREE_CODE (t1))
{
case TEMPLATE_TEMPLATE_PARM:
case BOUND_TEMPLATE_TEMPLATE_PARM:
if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
|| TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
return 0;
if (! comp_template_parms
(DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
return 0;
if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
return 1;
/* Don't check inheritance. */
strict = COMPARE_STRICT;
/* fall through */
case RECORD_TYPE:
case UNION_TYPE:
if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
&& (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
|| TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM))
val = comp_template_args (TYPE_TI_ARGS (t1),
TYPE_TI_ARGS (t2));
look_hard:
if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
val = 1;
else if ((strict & COMPARE_RELAXED) && DERIVED_FROM_P (t2, t1))
val = 1;
break;
case OFFSET_TYPE:
val = (comptypes (build_pointer_type (TYPE_OFFSET_BASETYPE (t1)),
build_pointer_type (TYPE_OFFSET_BASETYPE (t2)), strict)
&& comptypes (TREE_TYPE (t1), TREE_TYPE (t2), strict));
break;
case METHOD_TYPE:
if (! comp_except_specs (TYPE_RAISES_EXCEPTIONS (t1),
TYPE_RAISES_EXCEPTIONS (t2), 1))
return 0;
/* This case is anti-symmetrical!
One can pass a base member (or member function)
to something expecting a derived member (or member function),
but not vice-versa! */
val = (comptypes (TREE_TYPE (t1), TREE_TYPE (t2), strict)
&& compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)));
break;
case POINTER_TYPE:
case REFERENCE_TYPE:
t1 = TREE_TYPE (t1);
t2 = TREE_TYPE (t2);
/* first, check whether the referred types match with the
required level of strictness */
val = comptypes (t1, t2, strict);
if (val)
break;
if (TREE_CODE (t1) == RECORD_TYPE
&& TREE_CODE (t2) == RECORD_TYPE)
goto look_hard;
break;
case FUNCTION_TYPE:
if (! comp_except_specs (TYPE_RAISES_EXCEPTIONS (t1),
TYPE_RAISES_EXCEPTIONS (t2), 1))
return 0;
val = ((TREE_TYPE (t1) == TREE_TYPE (t2)
|| comptypes (TREE_TYPE (t1), TREE_TYPE (t2), strict))
&& compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)));
break;
case ARRAY_TYPE:
/* Target types must match incl. qualifiers. We use ORIG_STRICT
here since this is the one place where
COMPARE_REDECLARATION should be used. */
val = comp_array_types (comptypes, t1, t2, orig_strict);
break;
case TEMPLATE_TYPE_PARM:
return TEMPLATE_TYPE_IDX (t1) == TEMPLATE_TYPE_IDX (t2)
&& TEMPLATE_TYPE_LEVEL (t1) == TEMPLATE_TYPE_LEVEL (t2);
case TYPENAME_TYPE:
if (cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
TYPENAME_TYPE_FULLNAME (t2)) < 1)
return 0;
return same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2));
case UNBOUND_CLASS_TEMPLATE:
if (cp_tree_equal (TYPE_IDENTIFIER (t1),
TYPE_IDENTIFIER (t2)) < 1)
return 0;
return same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2));
case COMPLEX_TYPE:
return same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
default:
break;
}
return attrval == 2 && val == 1 ? 2 : val;
}
/* Subroutine of comp_target-types. Make sure that the cv-quals change
only in the same direction as the target type. */
static int
comp_cv_target_types (ttl, ttr, nptrs)
tree ttl, ttr;
int nptrs;
{
int t;
if (!at_least_as_qualified_p (ttl, ttr)
&& !at_least_as_qualified_p (ttr, ttl))
/* The qualifications are incomparable. */
return 0;
if (TYPE_MAIN_VARIANT (ttl) == TYPE_MAIN_VARIANT (ttr))
return more_qualified_p (ttr, ttl) ? -1 : 1;
t = comp_target_types (ttl, ttr, nptrs);
if ((t == 1 && at_least_as_qualified_p (ttl, ttr))
|| (t == -1 && at_least_as_qualified_p (ttr, ttl)))
return t;
return 0;
}
/* Return 1 or -1 if TTL and TTR are pointers to types that are equivalent,
ignoring their qualifiers, 0 if not. Return 1 means that TTR can be
converted to TTL. Return -1 means that TTL can be converted to TTR but
not vice versa.
NPTRS is the number of pointers we can strip off and keep cool.
This is used to permit (for aggr A, aggr B) A, B* to convert to A*,
but to not permit B** to convert to A**.
This should go away. Callers should use can_convert or something
similar instead. (jason 17 Apr 1997) */
int
comp_target_types (ttl, ttr, nptrs)
tree ttl, ttr;
int nptrs;
{
ttl = TYPE_MAIN_VARIANT (ttl);
ttr = TYPE_MAIN_VARIANT (ttr);
if (same_type_p (ttl, ttr))
return 1;
if (TREE_CODE (ttr) != TREE_CODE (ttl))
return 0;
if ((TREE_CODE (ttr) == POINTER_TYPE
|| TREE_CODE (ttr) == REFERENCE_TYPE)
/* If we get a pointer with nptrs == 0, we don't allow any tweaking
of the type pointed to. This is necessary for reference init
semantics. We won't get here from a previous call with nptrs == 1;
for multi-level pointers we end up in comp_ptr_ttypes. */
&& nptrs > 0)
{
int is_ptr = TREE_CODE (ttr) == POINTER_TYPE;
ttl = TREE_TYPE (ttl);
ttr = TREE_TYPE (ttr);
if (is_ptr)
{
if (TREE_CODE (ttl) == UNKNOWN_TYPE
|| TREE_CODE (ttr) == UNKNOWN_TYPE)
return 1;
else if (TREE_CODE (ttl) == VOID_TYPE
&& TREE_CODE (ttr) != FUNCTION_TYPE
&& TREE_CODE (ttr) != METHOD_TYPE
&& TREE_CODE (ttr) != OFFSET_TYPE)
return 1;
else if (TREE_CODE (ttr) == VOID_TYPE
&& TREE_CODE (ttl) != FUNCTION_TYPE
&& TREE_CODE (ttl) != METHOD_TYPE
&& TREE_CODE (ttl) != OFFSET_TYPE)
return -1;
else if (TREE_CODE (ttl) == POINTER_TYPE
|| TREE_CODE (ttl) == ARRAY_TYPE)
{
if (comp_ptr_ttypes (ttl, ttr))
return 1;
else if (comp_ptr_ttypes (ttr, ttl))
return -1;
return 0;
}
}
/* Const and volatile mean something different for function types,
so the usual checks are not appropriate. */
if (TREE_CODE (ttl) == FUNCTION_TYPE || TREE_CODE (ttl) == METHOD_TYPE)
return comp_target_types (ttl, ttr, nptrs - 1);
return comp_cv_target_types (ttl, ttr, nptrs - 1);
}
if (TREE_CODE (ttr) == ARRAY_TYPE)
return comp_array_types (comp_target_types, ttl, ttr, COMPARE_STRICT);
else if (TREE_CODE (ttr) == FUNCTION_TYPE || TREE_CODE (ttr) == METHOD_TYPE)
{
tree argsl, argsr;
int saw_contra = 0;
if (pedantic)
{
if (!same_type_p (TREE_TYPE (ttl), TREE_TYPE (ttr)))
return 0;
}
else
{
switch (comp_target_types (TREE_TYPE (ttl), TREE_TYPE (ttr), -1))
{
case 0:
return 0;
case -1:
saw_contra = 1;
}
}
argsl = TYPE_ARG_TYPES (ttl);
argsr = TYPE_ARG_TYPES (ttr);
/* Compare 'this' here, not in comp_target_parms. */
if (TREE_CODE (ttr) == METHOD_TYPE)
{
tree tl = TYPE_METHOD_BASETYPE (ttl);
tree tr = TYPE_METHOD_BASETYPE (ttr);
if (!same_or_base_type_p (tr, tl))
{
if (same_or_base_type_p (tl, tr))
saw_contra = 1;
else
return 0;
}
argsl = TREE_CHAIN (argsl);
argsr = TREE_CHAIN (argsr);
}
switch (comp_target_parms (argsl, argsr))
{
case 0:
return 0;
case -1:
saw_contra = 1;
}
return saw_contra ? -1 : 1;
}
/* for C++ */
else if (TREE_CODE (ttr) == OFFSET_TYPE)
{
int base;
/* Contravariance: we can assign a pointer to base member to a pointer
to derived member. Note difference from simple pointer case, where
we can pass a pointer to derived to a pointer to base. */
if (same_or_base_type_p (TYPE_OFFSET_BASETYPE (ttr),
TYPE_OFFSET_BASETYPE (ttl)))
base = 1;
else if (same_or_base_type_p (TYPE_OFFSET_BASETYPE (ttl),
TYPE_OFFSET_BASETYPE (ttr)))
{
tree tmp = ttl;
ttl = ttr;
ttr = tmp;
base = -1;
}
else
return 0;
ttl = TREE_TYPE (ttl);
ttr = TREE_TYPE (ttr);
if (TREE_CODE (ttl) == POINTER_TYPE
|| TREE_CODE (ttl) == ARRAY_TYPE)
{
if (comp_ptr_ttypes (ttl, ttr))
return base;
return 0;
}
else
{
if (comp_cv_target_types (ttl, ttr, nptrs) == 1)
return base;
return 0;
}
}
else if (IS_AGGR_TYPE (ttl))
{
if (nptrs < 0)
return 0;
if (same_or_base_type_p (build_pointer_type (ttl),
build_pointer_type (ttr)))
return 1;
if (same_or_base_type_p (build_pointer_type (ttr),
build_pointer_type (ttl)))
return -1;
return 0;
}
return 0;
}
/* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
int
at_least_as_qualified_p (type1, type2)
tree type1;
tree type2;
{
/* All qualifiers for TYPE2 must also appear in TYPE1. */
return ((cp_type_quals (type1) & cp_type_quals (type2))
== cp_type_quals (type2));
}
/* Returns 1 if TYPE1 is more qualified than TYPE2. */
int
more_qualified_p (type1, type2)
tree type1;
tree type2;
{
return (cp_type_quals (type1) != cp_type_quals (type2)
&& at_least_as_qualified_p (type1, type2));
}
/* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
more cv-qualified that TYPE1, and 0 otherwise. */
int
comp_cv_qualification (type1, type2)
tree type1;
tree type2;
{
if (cp_type_quals (type1) == cp_type_quals (type2))
return 0;
if (at_least_as_qualified_p (type1, type2))
return 1;
else if (at_least_as_qualified_p (type2, type1))
return -1;
return 0;
}
/* Returns 1 if the cv-qualification signature of TYPE1 is a proper
subset of the cv-qualification signature of TYPE2, and the types
are similar. Returns -1 if the other way 'round, and 0 otherwise. */
int
comp_cv_qual_signature (type1, type2)
tree type1;
tree type2;
{
if (comp_ptr_ttypes_real (type2, type1, -1))
return 1;
else if (comp_ptr_ttypes_real (type1, type2, -1))
return -1;
else
return 0;
}
/* If two types share a common base type, return that basetype.
If there is not a unique most-derived base type, this function
returns ERROR_MARK_NODE. */
static tree
common_base_type (tt1, tt2)
tree tt1, tt2;
{
tree best = NULL_TREE;
int i;
/* If one is a baseclass of another, that's good enough. */
if (UNIQUELY_DERIVED_FROM_P (tt1, tt2))
return tt1;
if (UNIQUELY_DERIVED_FROM_P (tt2, tt1))
return tt2;
/* Otherwise, try to find a unique baseclass of TT1
that is shared by TT2, and follow that down. */
for (i = CLASSTYPE_N_BASECLASSES (tt1)-1; i >= 0; i--)
{
tree basetype = TYPE_BINFO_BASETYPE (tt1, i);
tree trial = common_base_type (basetype, tt2);
if (trial)
{
if (trial == error_mark_node)
return trial;
if (best == NULL_TREE)
best = trial;
else if (best != trial)
return error_mark_node;
}
}
/* Same for TT2. */
for (i = CLASSTYPE_N_BASECLASSES (tt2)-1; i >= 0; i--)
{
tree basetype = TYPE_BINFO_BASETYPE (tt2, i);
tree trial = common_base_type (tt1, basetype);
if (trial)
{
if (trial == error_mark_node)
return trial;
if (best == NULL_TREE)
best = trial;
else if (best != trial)
return error_mark_node;
}
}
return best;
}
/* Subroutines of `comptypes'. */
/* Return 1 if two parameter type lists PARMS1 and PARMS2 are
equivalent in the sense that functions with those parameter types
can have equivalent types. The two lists must be equivalent,
element by element.
C++: See comment above about TYPE1, TYPE2. */
int
compparms (parms1, parms2)
tree parms1, parms2;
{
register tree t1 = parms1, t2 = parms2;
/* An unspecified parmlist matches any specified parmlist
whose argument types don't need default promotions. */
while (1)
{
if (t1 == 0 && t2 == 0)
return 1;
/* If one parmlist is shorter than the other,
they fail to match. */
if (t1 == 0 || t2 == 0)
return 0;
if (!same_type_p (TREE_VALUE (t2), TREE_VALUE (t1)))
return 0;
t1 = TREE_CHAIN (t1);
t2 = TREE_CHAIN (t2);
}
}
/* This really wants return whether or not parameter type lists
would make their owning functions assignment compatible or not.
The return value is like for comp_target_types.
This should go away, possibly with the exception of the empty parmlist
conversion; there are no conversions between function types in C++.
(jason 17 Apr 1997) */
static int
comp_target_parms (parms1, parms2)
tree parms1, parms2;
{
register tree t1 = parms1, t2 = parms2;
int warn_contravariance = 0;
/* In C, an unspecified parmlist matches any specified parmlist
whose argument types don't need default promotions. This is not
true for C++, but let's do it anyway for unfixed headers. */
if (t1 == 0 && t2 != 0)
{
pedwarn ("ISO C++ prohibits conversion from `%#T' to `(...)'",
parms2);
return self_promoting_args_p (t2);
}
if (t2 == 0)
return self_promoting_args_p (t1);
for (; t1 || t2; t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
{
tree p1, p2;
/* If one parmlist is shorter than the other,
they fail to match, unless STRICT is <= 0. */
if (t1 == 0 || t2 == 0)
return 0;
p1 = TREE_VALUE (t1);
p2 = TREE_VALUE (t2);
if (same_type_p (p1, p2))
continue;
if (pedantic)
return 0;
if ((TREE_CODE (p1) == POINTER_TYPE && TREE_CODE (p2) == POINTER_TYPE)
|| (TREE_CODE (p1) == REFERENCE_TYPE
&& TREE_CODE (p2) == REFERENCE_TYPE))
{
/* The following is wrong for contravariance,
but many programs depend on it. */
if (TREE_TYPE (p1) == void_type_node)
continue;
if (TREE_TYPE (p2) == void_type_node)
{
warn_contravariance = 1;
continue;
}
if (IS_AGGR_TYPE (TREE_TYPE (p1))
&& !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (p1),
TREE_TYPE (p2)))
return 0;
}
/* Note backwards order due to contravariance. */
if (comp_target_types (p2, p1, 1) <= 0)
{
if (comp_target_types (p1, p2, 1) > 0)
{
warn_contravariance = 1;
continue;
}
return 0;
}
}
return warn_contravariance ? -1 : 1;
}
/* Compute the value of the `sizeof' operator. */
tree
c_sizeof (type)
tree type;
{
enum tree_code code = TREE_CODE (type);
tree size;
if (processing_template_decl)
return build_min_nt (SIZEOF_EXPR, type);
if (code == FUNCTION_TYPE)
{
if (pedantic || warn_pointer_arith)
pedwarn ("ISO C++ forbids applying `sizeof' to a function type");
size = size_one_node;
}
else if (code == METHOD_TYPE)
{
if (pedantic || warn_pointer_arith)
pedwarn ("ISO C++ forbids applying `sizeof' to a member function");
size = size_one_node;
}
else if (code == VOID_TYPE)
{
if (pedantic || warn_pointer_arith)
pedwarn ("ISO C++ forbids applying `sizeof' to type `void' which is an incomplete type");
size = size_one_node;
}
else if (code == ERROR_MARK)
size = size_one_node;
else
{
/* ARM $5.3.2: ``When applied to a reference, the result is the
size of the referenced object.'' */
if (code == REFERENCE_TYPE)
type = TREE_TYPE (type);
if (code == OFFSET_TYPE)
{
error ("`sizeof' applied to non-static member");
size = size_zero_node;
}
else if (!COMPLETE_TYPE_P (complete_type (type)))
{
error ("`sizeof' applied to incomplete type `%T'", type);
size = size_zero_node;
}
else
/* Convert in case a char is more than one unit. */
size = size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
size_int (TYPE_PRECISION (char_type_node)
/ BITS_PER_UNIT));
}
/* SIZE will have an integer type with TYPE_IS_SIZETYPE set.
TYPE_IS_SIZETYPE means that certain things (like overflow) will
never happen. However, this node should really have type
`size_t', which is just a typedef for an ordinary integer type. */
size = fold (build1 (NOP_EXPR, c_size_type_node, size));
my_friendly_assert (!TYPE_IS_SIZETYPE (TREE_TYPE (size)),
20001021);
return size;
}
tree
expr_sizeof (e)
tree e;
{
if (processing_template_decl)
return build_min_nt (SIZEOF_EXPR, e);
if (TREE_CODE (e) == COMPONENT_REF
&& DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
error ("sizeof applied to a bit-field");
if (is_overloaded_fn (e))
{
pedwarn ("ISO C++ forbids applying `sizeof' to an expression of function type");
return c_sizeof (char_type_node);
}
else if (type_unknown_p (e))
{
incomplete_type_error (e, TREE_TYPE (e));
return c_sizeof (char_type_node);
}
/* It's illegal to say `sizeof (X::i)' for `i' a non-static data
member unless you're in a non-static member of X. So hand off to
resolve_offset_ref. [expr.prim] */
else if (TREE_CODE (e) == OFFSET_REF)
e = resolve_offset_ref (e);
if (e == error_mark_node)
return e;
return c_sizeof (TREE_TYPE (e));
}
tree
c_sizeof_nowarn (type)
tree type;
{
enum tree_code code = TREE_CODE (type);
tree size;
if (code == FUNCTION_TYPE
|| code == METHOD_TYPE
|| code == VOID_TYPE
|| code == ERROR_MARK)
size = size_one_node;
else
{
if (code == REFERENCE_TYPE)
type = TREE_TYPE (type);
if (!COMPLETE_TYPE_P (type))
size = size_zero_node;
else
/* Convert in case a char is more than one unit. */
size = size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
size_int (TYPE_PRECISION (char_type_node)
/ BITS_PER_UNIT));
}
/* SIZE will have an integer type with TYPE_IS_SIZETYPE set.
TYPE_IS_SIZETYPE means that certain things (like overflow) will
never happen. However, this node should really have type
`size_t', which is just a typedef for an ordinary integer type. */
size = fold (build1 (NOP_EXPR, c_size_type_node, size));
my_friendly_assert (!TYPE_IS_SIZETYPE (TREE_TYPE (size)),
20001021);
return size;
}
/* Perform the array-to-pointer and function-to-pointer conversions
for EXP.
In addition, references are converted to lvalues and manifest
constants are replaced by their values. */
tree
decay_conversion (exp)
tree exp;
{
register tree type;
register enum tree_code code;
if (TREE_CODE (exp) == OFFSET_REF)
exp = resolve_offset_ref (exp);
type = TREE_TYPE (exp);
code = TREE_CODE (type);
if (code == REFERENCE_TYPE)
{
exp = convert_from_reference (exp);
type = TREE_TYPE (exp);
code = TREE_CODE (type);
}
if (type == error_mark_node)
return error_mark_node;
if (type_unknown_p (exp))
{
incomplete_type_error (exp, TREE_TYPE (exp));
return error_mark_node;
}
/* Constants can be used directly unless they're not loadable. */
if (TREE_CODE (exp) == CONST_DECL)
exp = DECL_INITIAL (exp);
/* Replace a nonvolatile const static variable with its value. We
don't do this for arrays, though; we want the address of the
first element of the array, not the address of the first element
of its initializing constant. */
else if (code != ARRAY_TYPE)
{
exp = decl_constant_value (exp);
type = TREE_TYPE (exp);
}
/* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
if (code == VOID_TYPE)
{
error ("void value not ignored as it ought to be");
return error_mark_node;
}
if (code == METHOD_TYPE)
my_friendly_abort (990506);
if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
return build_unary_op (ADDR_EXPR, exp, 0);
if (code == ARRAY_TYPE)
{
register tree adr;
tree ptrtype;
if (TREE_CODE (exp) == INDIRECT_REF)
{
/* Stripping away the INDIRECT_REF is not the right
thing to do for references... */
tree inner = TREE_OPERAND (exp, 0);
if (TREE_CODE (TREE_TYPE (inner)) == REFERENCE_TYPE)
{
inner = build1 (CONVERT_EXPR,
build_pointer_type (TREE_TYPE
(TREE_TYPE (inner))),
inner);
TREE_CONSTANT (inner) = TREE_CONSTANT (TREE_OPERAND (inner, 0));
}
return cp_convert (build_pointer_type (TREE_TYPE (type)), inner);
}
if (TREE_CODE (exp) == COMPOUND_EXPR)
{
tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
return build (COMPOUND_EXPR, TREE_TYPE (op1),
TREE_OPERAND (exp, 0), op1);
}
if (!lvalue_p (exp)
&& ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
{
error ("invalid use of non-lvalue array");
return error_mark_node;
}
ptrtype = build_pointer_type (TREE_TYPE (type));
if (TREE_CODE (exp) == VAR_DECL)
{
/* ??? This is not really quite correct
in that the type of the operand of ADDR_EXPR
is not the target type of the type of the ADDR_EXPR itself.
Question is, can this lossage be avoided? */
adr = build1 (ADDR_EXPR, ptrtype, exp);
if (mark_addressable (exp) == 0)
return error_mark_node;
TREE_CONSTANT (adr) = staticp (exp);
TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
return adr;
}
/* This way is better for a COMPONENT_REF since it can
simplify the offset for a component. */
adr = build_unary_op (ADDR_EXPR, exp, 1);
return cp_convert (ptrtype, adr);
}
/* [basic.lval]: Class rvalues can have cv-qualified types; non-class
rvalues always have cv-unqualified types. */
if (! CLASS_TYPE_P (type))
exp = cp_convert (TYPE_MAIN_VARIANT (type), exp);
return exp;
}
tree
default_conversion (exp)
tree exp;
{
tree type;
enum tree_code code;
exp = decay_conversion (exp);
type = TREE_TYPE (exp);
code = TREE_CODE (type);
if (INTEGRAL_CODE_P (code))
{
tree t = type_promotes_to (type);
if (t != type)
return cp_convert (t, exp);
}
return exp;
}
/* Take the address of an inline function without setting TREE_ADDRESSABLE
or TREE_USED. */
tree
inline_conversion (exp)
tree exp;
{
if (TREE_CODE (exp) == FUNCTION_DECL)
exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
return exp;
}
/* Returns nonzero iff exp is a STRING_CST or the result of applying
decay_conversion to one. */
int
string_conv_p (totype, exp, warn)
tree totype, exp;
int warn;
{
tree t;
if (! flag_const_strings || TREE_CODE (totype) != POINTER_TYPE)
return 0;
t = TREE_TYPE (totype);
if (!same_type_p (t, char_type_node)
&& !same_type_p (t, wchar_type_node))
return 0;
if (TREE_CODE (exp) == STRING_CST)
{
/* Make sure that we don't try to convert between char and wchar_t. */
if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
return 0;
}
else
{
/* Is this a string constant which has decayed to 'const char *'? */
t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
if (!same_type_p (TREE_TYPE (exp), t))
return 0;
STRIP_NOPS (exp);
if (TREE_CODE (exp) != ADDR_EXPR
|| TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
return 0;
}
/* This warning is not very useful, as it complains about printf. */
if (warn && warn_write_strings)
warning ("deprecated conversion from string constant to `%T'", totype);
return 1;
}
tree
build_object_ref (datum, basetype, field)
tree datum, basetype, field;
{
tree dtype;
if (datum == error_mark_node)
return error_mark_node;
dtype = TREE_TYPE (datum);
if (TREE_CODE (dtype) == REFERENCE_TYPE)
dtype = TREE_TYPE (dtype);
if (! IS_AGGR_TYPE_CODE (TREE_CODE (dtype)))
{
error ("request for member `%T::%D' in expression of non-aggregate type `%T'",
basetype, field, dtype);
return error_mark_node;
}
else if (is_aggr_type (basetype, 1))
{
tree binfo = binfo_or_else (basetype, dtype);
if (binfo)
return build_x_component_ref (build_scoped_ref (datum, basetype),
field, binfo, 1);
}
return error_mark_node;
}
/* Like `build_component_ref, but uses an already found field, and converts
from a reference. Must compute access for current_class_ref.
Otherwise, ok. */
tree
build_component_ref_1 (datum, field, protect)
tree datum, field;
int protect;
{
return convert_from_reference
(build_component_ref (datum, field, NULL_TREE, protect));
}
/* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
can, for example, use as an lvalue. This code used to be in
unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
expressions, where we're dealing with aggregates. But now it's again only
called from unary_complex_lvalue. The case (in particular) that led to
this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
get it there. */
static tree
rationalize_conditional_expr (code, t)
enum tree_code code;
tree t;
{
/* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
the first operand is always the one to be used if both operands
are equal, so we know what conditional expression this used to be. */
if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
{
return
build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
? LE_EXPR : GE_EXPR),
TREE_OPERAND (t, 0),
TREE_OPERAND (t, 1)),
build_unary_op (code, TREE_OPERAND (t, 0), 0),
build_unary_op (code, TREE_OPERAND (t, 1), 0));
}
return
build_conditional_expr (TREE_OPERAND (t, 0),
build_unary_op (code, TREE_OPERAND (t, 1), 0),
build_unary_op (code, TREE_OPERAND (t, 2), 0));
}
/* Given the TYPE of an anonymous union field inside T, return the
FIELD_DECL for the field. If not found return NULL_TREE. Because
anonymous unions can nest, we must also search all anonymous unions
that are directly reachable. */
static tree
lookup_anon_field (t, type)
tree t, type;
{
tree field;
for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
{
if (TREE_STATIC (field))
continue;
if (TREE_CODE (field) != FIELD_DECL)
continue;
/* If we find it directly, return the field. */
if (DECL_NAME (field) == NULL_TREE
&& type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
{
return field;
}
/* Otherwise, it could be nested, search harder. */
if (DECL_NAME (field) == NULL_TREE
&& ANON_AGGR_TYPE_P (TREE_TYPE (field)))
{
tree subfield = lookup_anon_field (TREE_TYPE (field), type);
if (subfield)
return subfield;
}
}
return NULL_TREE;
}
/* Build a COMPONENT_REF for a given DATUM, and it's member COMPONENT.
COMPONENT can be an IDENTIFIER_NODE that is the name of the member
that we are interested in, or it can be a FIELD_DECL. */
tree
build_component_ref (datum, component, basetype_path, protect)
tree datum, component, basetype_path;
int protect;
{
register tree basetype;
register enum tree_code code;
register tree field = NULL;
register tree ref;
tree field_type;
int type_quals;
if (processing_template_decl)
return build_min_nt (COMPONENT_REF, datum, component);
if (datum == error_mark_node
|| TREE_TYPE (datum) == error_mark_node)
return error_mark_node;
/* BASETYPE holds the type of the class containing the COMPONENT. */
basetype = TYPE_MAIN_VARIANT (TREE_TYPE (datum));
/* If DATUM is a COMPOUND_EXPR or COND_EXPR, move our reference
inside it. */
switch (TREE_CODE (datum))
{
case COMPOUND_EXPR:
{
tree value = build_component_ref (TREE_OPERAND (datum, 1), component,
basetype_path, protect);
return build (COMPOUND_EXPR, TREE_TYPE (value),
TREE_OPERAND (datum, 0), value);
}
case COND_EXPR:
return build_conditional_expr
(TREE_OPERAND (datum, 0),
build_component_ref (TREE_OPERAND (datum, 1), component,
basetype_path, protect),
build_component_ref (TREE_OPERAND (datum, 2), component,
basetype_path, protect));
case TEMPLATE_DECL:
error ("invalid use of %D", datum);
datum = error_mark_node;
break;
default:
break;
}
code = TREE_CODE (basetype);
if (code == REFERENCE_TYPE)
{
datum = convert_from_reference (datum);
basetype = TYPE_MAIN_VARIANT (TREE_TYPE (datum));
code = TREE_CODE (basetype);
}
if (TREE_CODE (datum) == OFFSET_REF)
{
datum = resolve_offset_ref (datum);
basetype = TYPE_MAIN_VARIANT (TREE_TYPE (datum));
code = TREE_CODE (basetype);
}
/* First, see if there is a field or component with name COMPONENT. */
if (TREE_CODE (component) == TREE_LIST)
{
/* I could not trigger this code. MvL */
my_friendly_abort (980326);
#ifdef DEAD
my_friendly_assert (!(TREE_CHAIN (component) == NULL_TREE
&& DECL_CHAIN (TREE_VALUE (component)) == NULL_TREE), 309);
#endif
return build (COMPONENT_REF, TREE_TYPE (component), datum, component);
}
if (! IS_AGGR_TYPE_CODE (code))
{
if (code != ERROR_MARK)
error ("request for member `%D' in `%E', which is of non-aggregate type `%T'",
component, datum, basetype);
return error_mark_node;
}
if (!complete_type_or_else (basetype, datum))
return error_mark_node;
if (TREE_CODE (component) == BIT_NOT_EXPR)
{
if (TYPE_IDENTIFIER (basetype) != TREE_OPERAND (component, 0))
{
error ("destructor specifier `%T::~%T' must have matching names",
basetype, TREE_OPERAND (component, 0));
return error_mark_node;
}
if (! TYPE_HAS_DESTRUCTOR (basetype))
{
error ("type `%T' has no destructor", basetype);
return error_mark_node;
}
return TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (basetype), 1);
}
/* Look up component name in the structure type definition. */
if (TYPE_VFIELD (basetype)
&& DECL_NAME (TYPE_VFIELD (basetype)) == component)
/* Special-case this because if we use normal lookups in an ambiguous
hierarchy, the compiler will abort (because vptr lookups are
not supposed to be ambiguous. */
field = TYPE_VFIELD (basetype);
else if (TREE_CODE (component) == FIELD_DECL)
field = component;
else if (TREE_CODE (component) == TYPE_DECL)
{
error ("invalid use of type decl `%#D' as expression", component);
return error_mark_node;
}
else if (TREE_CODE (component) == TEMPLATE_DECL)
{
error ("invalid use of template `%#D' as expression", component);
return error_mark_node;
}
else
{
tree name = component;
if (TREE_CODE (component) == VAR_DECL)
name = DECL_NAME (component);
if (TREE_CODE (component) == NAMESPACE_DECL)
/* Source is in error, but produce a sensible diagnostic. */
name = DECL_NAME (component);
if (basetype_path == NULL_TREE)
basetype_path = TYPE_BINFO (basetype);
field = lookup_field (basetype_path, name,
protect && !VFIELD_NAME_P (name), 0);
if (field == error_mark_node)
return error_mark_node;
if (field == NULL_TREE)
{
/* Not found as a data field, look for it as a method. If found,
then if this is the only possible one, return it, else
report ambiguity error. */
tree fndecls = lookup_fnfields (basetype_path, name, 1);
if (fndecls == error_mark_node)
return error_mark_node;
if (fndecls)
{
/* If the function is unique and static, we can resolve it
now. Otherwise, we have to wait and see what context it is
used in; a component_ref involving a non-static member
function can only be used in a call (expr.ref). */
if (TREE_CHAIN (fndecls) == NULL_TREE
&& TREE_CODE (TREE_VALUE (fndecls)) == FUNCTION_DECL)
{
if (DECL_STATIC_FUNCTION_P (TREE_VALUE (fndecls)))
{
tree fndecl = TREE_VALUE (fndecls);
enforce_access (basetype_path, fndecl);
mark_used (fndecl);
return fndecl;
}
else
{
/* A unique non-static member function. Other parts
of the compiler expect something with
unknown_type_node to be really overloaded, so
let's oblige. */
TREE_VALUE (fndecls)
= ovl_cons (TREE_VALUE (fndecls), NULL_TREE);
}
}
ref = build (COMPONENT_REF, unknown_type_node,
datum, TREE_VALUE (fndecls));
return ref;
}
error ("`%#T' has no member named `%D'", basetype, name);
return error_mark_node;
}
else if (TREE_TYPE (field) == error_mark_node)
return error_mark_node;
if (TREE_CODE (field) != FIELD_DECL)
{
if (TREE_CODE (field) == TYPE_DECL)
pedwarn ("invalid use of type decl `%#D' as expression", field);
else if (DECL_RTL (field) != 0)
mark_used (field);
else
TREE_USED (field) = 1;
/* Do evaluate the object when accessing a static member. */
if (TREE_SIDE_EFFECTS (datum))
field = build (COMPOUND_EXPR, TREE_TYPE (field), datum, field);
return field;
}
}
/* See if we have to do any conversions so that we pick up the field from the
right context. */
if (DECL_FIELD_CONTEXT (field) != basetype)
{
tree context = DECL_FIELD_CONTEXT (field);
tree base = context;
while (!same_type_p (base, basetype) && TYPE_NAME (base)
&& ANON_AGGR_TYPE_P (base))
base = TYPE_CONTEXT (base);
/* Handle base classes here... */
if (base != basetype && TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (basetype))
{
tree binfo = lookup_base (TREE_TYPE (datum), base, ba_check, NULL);
if (TREE_CODE (datum) == INDIRECT_REF
&& integer_zerop (TREE_OPERAND (datum, 0)))
{
error ("invalid reference to NULL ptr, use ptr-to-member instead");
return error_mark_node;
}
datum = build_base_path (PLUS_EXPR, datum, binfo, 1);
if (datum == error_mark_node)
return error_mark_node;
}
basetype = base;
/* Handle things from anon unions here... */
if (TYPE_NAME (context) && ANON_AGGR_TYPE_P (context))
{
tree subfield = lookup_anon_field (basetype, context);
tree subdatum = build_component_ref (datum, subfield,
basetype_path, protect);
return build_component_ref (subdatum, field, basetype_path, protect);
}
}
/* Compute the type of the field, as described in [expr.ref]. */
type_quals = TYPE_UNQUALIFIED;
field_type = TREE_TYPE (field);
if (TREE_CODE (field_type) == REFERENCE_TYPE)
/* The standard says that the type of the result should be the
type referred to by the reference. But for now, at least, we
do the conversion from reference type later. */
;
else
{
type_quals = (cp_type_quals (field_type)
| cp_type_quals (TREE_TYPE (datum)));
/* A field is const (volatile) if the enclosing object, or the
field itself, is const (volatile). But, a mutable field is
not const, even within a const object. */
if (DECL_MUTABLE_P (field))
type_quals &= ~TYPE_QUAL_CONST;
field_type = cp_build_qualified_type (field_type, type_quals);
}
ref = fold (build (COMPONENT_REF, field_type, datum, field));
/* Mark the expression const or volatile, as appropriate. Even
though we've dealt with the type above, we still have to mark the
expression itself. */
if (type_quals & TYPE_QUAL_CONST)
TREE_READONLY (ref) = 1;
else if (type_quals & TYPE_QUAL_VOLATILE)
TREE_THIS_VOLATILE (ref) = 1;
return ref;
}
/* Variant of build_component_ref for use in expressions, which should
never have REFERENCE_TYPE. */
tree
build_x_component_ref (datum, component, basetype_path, protect)
tree datum, component, basetype_path;
int protect;
{
tree t = build_component_ref (datum, component, basetype_path, protect);
if (! processing_template_decl)
t = convert_from_reference (t);
return t;
}
/* Given an expression PTR for a pointer, return an expression
for the value pointed to.
ERRORSTRING is the name of the operator to appear in error messages.
This function may need to overload OPERATOR_FNNAME.
Must also handle REFERENCE_TYPEs for C++. */
tree
build_x_indirect_ref (ptr, errorstring)
tree ptr;
const char *errorstring;
{
tree rval;
if (processing_template_decl)
return build_min_nt (INDIRECT_REF, ptr);
rval = build_opfncall (INDIRECT_REF, LOOKUP_NORMAL, ptr, NULL_TREE,
NULL_TREE);
if (rval)
return rval;
return build_indirect_ref (ptr, errorstring);
}
tree
build_indirect_ref (ptr, errorstring)
tree ptr;
const char *errorstring;
{
register tree pointer, type;
if (ptr == error_mark_node)
return error_mark_node;
if (ptr == current_class_ptr)
return current_class_ref;
pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
? ptr : default_conversion (ptr));
type = TREE_TYPE (pointer);
if (TYPE_PTR_P (type) || TREE_CODE (type) == REFERENCE_TYPE)
{
/* [expr.unary.op]
If the type of the expression is "pointer to T," the type
of the result is "T."
We must use the canonical variant because certain parts of
the back end, like fold, do pointer comparisons between
types. */
tree t = canonical_type_variant (TREE_TYPE (type));
if (VOID_TYPE_P (t))
{
/* A pointer to incomplete type (other than cv void) can be
dereferenced [expr.unary.op]/1 */
error ("`%T' is not a pointer-to-object type", type);
return error_mark_node;
}
else if (TREE_CODE (pointer) == ADDR_EXPR
&& !flag_volatile
&& same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
/* The POINTER was something like `&x'. We simplify `*&x' to
`x'. */
return TREE_OPERAND (pointer, 0);
else
{
tree ref = build1 (INDIRECT_REF, t, pointer);
/* We *must* set TREE_READONLY when dereferencing a pointer to const,
so that we get the proper error message if the result is used
to assign to. Also, &* is supposed to be a no-op. */
TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
TREE_SIDE_EFFECTS (ref)
= (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer)
|| flag_volatile);
return ref;
}
}
/* `pointer' won't be an error_mark_node if we were given a
pointer to member, so it's cool to check for this here. */
else if (TYPE_PTRMEM_P (type) || TYPE_PTRMEMFUNC_P (type))
error ("invalid use of `%s' on pointer to member", errorstring);
else if (pointer != error_mark_node)
{
if (errorstring)
error ("invalid type argument of `%s'", errorstring);
else
error ("invalid type argument");
}
return error_mark_node;
}
/* This handles expressions of the form "a[i]", which denotes
an array reference.
This is logically equivalent in C to *(a+i), but we may do it differently.
If A is a variable or a member, we generate a primitive ARRAY_REF.
This avoids forcing the array out of registers, and can work on
arrays that are not lvalues (for example, members of structures returned
by functions).
If INDEX is of some user-defined type, it must be converted to
integer type. Otherwise, to make a compatible PLUS_EXPR, it
will inherit the type of the array, which will be some pointer type. */
tree
build_array_ref (array, idx)
tree array, idx;
{
if (idx == 0)
{
error ("subscript missing in array reference");
return error_mark_node;
}
if (TREE_TYPE (array) == error_mark_node
|| TREE_TYPE (idx) == error_mark_node)
return error_mark_node;
/* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
inside it. */
switch (TREE_CODE (array))
{
case COMPOUND_EXPR:
{
tree value = build_array_ref (TREE_OPERAND (array, 1), idx);
return build (COMPOUND_EXPR, TREE_TYPE (value),
TREE_OPERAND (array, 0), value);
}
case COND_EXPR:
return build_conditional_expr
(TREE_OPERAND (array, 0),
build_array_ref (TREE_OPERAND (array, 1), idx),
build_array_ref (TREE_OPERAND (array, 2), idx));
default:
break;
}
if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE
&& TREE_CODE (array) != INDIRECT_REF)
{
tree rval, type;
/* Subscripting with type char is likely to lose
on a machine where chars are signed.
So warn on any machine, but optionally.
Don't warn for unsigned char since that type is safe.
Don't warn for signed char because anyone who uses that
must have done so deliberately. */
if (warn_char_subscripts
&& TYPE_MAIN_VARIANT (TREE_TYPE (idx)) == char_type_node)
warning ("array subscript has type `char'");
/* Apply default promotions *after* noticing character types. */
idx = default_conversion (idx);
if (TREE_CODE (TREE_TYPE (idx)) != INTEGER_TYPE)
{
error ("array subscript is not an integer");
return error_mark_node;
}
/* An array that is indexed by a non-constant
cannot be stored in a register; we must be able to do
address arithmetic on its address.
Likewise an array of elements of variable size. */
if (TREE_CODE (idx) != INTEGER_CST
|| (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
&& (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
!= INTEGER_CST)))
{
if (mark_addressable (array) == 0)
return error_mark_node;
}
/* An array that is indexed by a constant value which is not within
the array bounds cannot be stored in a register either; because we
would get a crash in store_bit_field/extract_bit_field when trying
to access a non-existent part of the register. */
if (TREE_CODE (idx) == INTEGER_CST
&& TYPE_VALUES (TREE_TYPE (array))
&& ! int_fits_type_p (idx, TYPE_VALUES (TREE_TYPE (array))))
{
if (mark_addressable (array) == 0)
return error_mark_node;
}
if (pedantic && !lvalue_p (array))
pedwarn ("ISO C++ forbids subscripting non-lvalue array");
/* Note in C++ it is valid to subscript a `register' array, since
it is valid to take the address of something with that
storage specification. */
if (extra_warnings)
{
tree foo = array;
while (TREE_CODE (foo) == COMPONENT_REF)
foo = TREE_OPERAND (foo, 0);
if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
warning ("subscripting array declared `register'");
}
type = TREE_TYPE (TREE_TYPE (array));
rval = build (ARRAY_REF, type, array, idx);
/* Array ref is const/volatile if the array elements are
or if the array is.. */
TREE_READONLY (rval)
|= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
TREE_SIDE_EFFECTS (rval)
|= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
TREE_THIS_VOLATILE (rval)
|= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
return require_complete_type (fold (rval));
}
{
tree ar = default_conversion (array);
tree ind = default_conversion (idx);
/* Put the integer in IND to simplify error checking. */
if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
{
tree temp = ar;
ar = ind;
ind = temp;
}
if (ar == error_mark_node)
return ar;
if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
{
error ("subscripted value is neither array nor pointer");
return error_mark_node;
}
if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
{
error ("array subscript is not an integer");
return error_mark_node;
}
return build_indirect_ref (cp_build_binary_op (PLUS_EXPR, ar, ind),
"array indexing");
}
}
/* Build a function call to function FUNCTION with parameters PARAMS.
PARAMS is a list--a chain of TREE_LIST nodes--in which the
TREE_VALUE of each node is a parameter-expression. The PARAMS do
not include any object pointer that may be required. FUNCTION's
data type may be a function type or a pointer-to-function.
For C++: If FUNCTION's data type is a TREE_LIST, then the tree list
is the list of possible methods that FUNCTION could conceivably
be. If the list of methods comes from a class, then it will be
a list of lists (where each element is associated with the class
that produced it), otherwise it will be a simple list (for
functions overloaded in global scope).
In the first case, TREE_VALUE (function) is the head of one of those
lists, and TREE_PURPOSE is the name of the function.
In the second case, TREE_PURPOSE (function) is the function's
name directly.
DECL is the class instance variable, usually CURRENT_CLASS_REF.
When calling a TEMPLATE_DECL, we don't require a complete return
type. */
tree
build_x_function_call (function, params, decl)
tree function, params, decl;
{
tree type;
tree template_id = NULL_TREE;
int is_method;
if (function == error_mark_node)
return error_mark_node;
if (processing_template_decl)
return build_min_nt (CALL_EXPR, function, params, NULL_TREE);
/* Save explicit template arguments if found */
if (TREE_CODE (function) == TEMPLATE_ID_EXPR)
{
template_id = function;
function = TREE_OPERAND (function, 0);
}
type = TREE_TYPE (function);
if (TREE_CODE (type) == OFFSET_TYPE
&& TREE_TYPE (type) == unknown_type_node
&& TREE_CODE (function) == TREE_LIST
&& TREE_CHAIN (function) == NULL_TREE)
{
/* Undo (Foo:bar)()... */
type = TYPE_OFFSET_BASETYPE (type);
function = TREE_VALUE (function);
my_friendly_assert (TREE_CODE (function) == TREE_LIST, 999);
my_friendly_assert (TREE_CHAIN (function) == NULL_TREE, 999);
function = TREE_VALUE (function);
if (TREE_CODE (function) == OVERLOAD)
function = OVL_FUNCTION (function);
my_friendly_assert (TREE_CODE (function) == FUNCTION_DECL, 999);
function = DECL_NAME (function);
return build_method_call (decl, function, params,
TYPE_BINFO (type), LOOKUP_NORMAL);
}
if (TREE_CODE (function) == OFFSET_REF
&& TREE_CODE (type) != METHOD_TYPE)
function = resolve_offset_ref (function);
if ((TREE_CODE (function) == FUNCTION_DECL
&& DECL_STATIC_FUNCTION_P (function))
|| (DECL_FUNCTION_TEMPLATE_P (function)
&& DECL_STATIC_FUNCTION_P (DECL_TEMPLATE_RESULT (function))))
return build_member_call (DECL_CONTEXT (function),
template_id
? template_id : DECL_NAME (function),
params);
is_method = ((TREE_CODE (function) == TREE_LIST
&& current_class_type != NULL_TREE
&& (IDENTIFIER_CLASS_VALUE (TREE_PURPOSE (function))
== function))
|| (TREE_CODE (function) == OVERLOAD
&& DECL_FUNCTION_MEMBER_P (OVL_CURRENT (function)))
|| TREE_CODE (function) == IDENTIFIER_NODE
|| TREE_CODE (type) == METHOD_TYPE
|| TYPE_PTRMEMFUNC_P (type));
/* A friend template. Make it look like a toplevel declaration. */
if (! is_method && TREE_CODE (function) == TEMPLATE_DECL)
function = ovl_cons (function, NULL_TREE);
/* Handle methods, friends, and overloaded functions, respectively. */
if (is_method)
{
tree basetype = NULL_TREE;
if (TREE_CODE (function) == OVERLOAD)
function = OVL_CURRENT (function);
if (TREE_CODE (function) == FUNCTION_DECL
|| DECL_FUNCTION_TEMPLATE_P (function))
{
basetype = DECL_CONTEXT (function);
if (DECL_NAME (function))
function = DECL_NAME (function);
else
function = TYPE_IDENTIFIER (DECL_CONTEXT (function));
}
else if (TREE_CODE (function) == TREE_LIST)
{
my_friendly_assert (TREE_CODE (TREE_VALUE (function))
== FUNCTION_DECL, 312);
basetype = DECL_CONTEXT (TREE_VALUE (function));
function = TREE_PURPOSE (function);
}
else if (TREE_CODE (function) != IDENTIFIER_NODE)
{
if (TREE_CODE (function) == OFFSET_REF)
{
if (TREE_OPERAND (function, 0))
decl = TREE_OPERAND (function, 0);
}
/* Call via a pointer to member function. */
if (decl == NULL_TREE)
{
error ("pointer to member function called, but not in class scope");
return error_mark_node;
}
/* What other type of POINTER_TYPE could this be? */
if (TREE_CODE (TREE_TYPE (function)) != POINTER_TYPE
&& ! TYPE_PTRMEMFUNC_P (TREE_TYPE (function))
&& TREE_CODE (function) != OFFSET_REF)
function = build (OFFSET_REF, TREE_TYPE (type), NULL_TREE,
function);
goto do_x_function;
}
/* this is an abbreviated method call.
must go through here in case it is a virtual function.
@@ Perhaps this could be optimized. */
if (basetype && (! current_class_type
|| ! DERIVED_FROM_P (basetype, current_class_type)))
return build_member_call (basetype, function, params);
if (decl == NULL_TREE)
{
if (current_class_type == NULL_TREE)
{
error ("object missing in call to method `%D'", function);
return error_mark_node;
}
/* Yow: call from a static member function. */
decl = build_dummy_object (current_class_type);
}
/* Put back explicit template arguments, if any. */
if (template_id)
function = template_id;
return build_method_call (decl, function, params,
NULL_TREE, LOOKUP_NORMAL);
}
else if (TREE_CODE (function) == COMPONENT_REF
&& type == unknown_type_node)
{
/* Undo what we did in build_component_ref. */
decl = TREE_OPERAND (function, 0);
function = TREE_OPERAND (function, 1);
function = DECL_NAME (OVL_CURRENT (function));
if (template_id)
{
TREE_OPERAND (template_id, 0) = function;
function = template_id;
}
return build_method_call (decl, function, params,
NULL_TREE, LOOKUP_NORMAL);
}
else if (really_overloaded_fn (function))
{
if (OVL_FUNCTION (function) == NULL_TREE)
{
error ("function `%D' declared overloaded, but no definitions appear with which to resolve it?!?",
TREE_PURPOSE (function));
return error_mark_node;
}
else
{
/* Put back explicit template arguments, if any. */
if (template_id)
function = template_id;
return build_new_function_call (function, params);
}
}
else
/* Remove a potential OVERLOAD around it */
function = OVL_CURRENT (function);
do_x_function:
if (TREE_CODE (function) == OFFSET_REF)
{
/* If the component is a data element (or a virtual function), we play
games here to make things work. */
tree decl_addr;
if (TREE_OPERAND (function, 0))
decl = TREE_OPERAND (function, 0);
else
decl = current_class_ref;
decl_addr = build_unary_op (ADDR_EXPR, decl, 0);
/* Sigh. OFFSET_REFs are being used for too many things.
They're being used both for -> and ->*, and we want to resolve
the -> cases here, but leave the ->*. We could use
resolve_offset_ref for those, too, but it would call
get_member_function_from_ptrfunc and decl_addr wouldn't get
updated properly. Nasty. */
if (TREE_CODE (TREE_OPERAND (function, 1)) == FIELD_DECL)
function = resolve_offset_ref (function);
else
function = TREE_OPERAND (function, 1);
function = get_member_function_from_ptrfunc (&decl_addr, function);
params = tree_cons (NULL_TREE, decl_addr, params);
return build_function_call (function, params);
}
type = TREE_TYPE (function);
if (type != error_mark_node)
{
if (TREE_CODE (type) == REFERENCE_TYPE)
type = TREE_TYPE (type);
if (IS_AGGR_TYPE (type))
return build_opfncall (CALL_EXPR, LOOKUP_NORMAL, function, params, NULL_TREE);
}
if (is_method)
{
tree fntype = TREE_TYPE (function);
tree ctypeptr = NULL_TREE;
/* Explicitly named method? */
if (TREE_CODE (function) == FUNCTION_DECL)
ctypeptr = build_pointer_type (DECL_CLASS_CONTEXT (function));
/* Expression with ptr-to-method type? It could either be a plain
usage, or it might be a case where the ptr-to-method is being
passed in as an argument. */
else if (TYPE_PTRMEMFUNC_P (fntype))
{
tree rec = TYPE_METHOD_BASETYPE (TREE_TYPE
(TYPE_PTRMEMFUNC_FN_TYPE (fntype)));
ctypeptr = build_pointer_type (rec);
}
/* Unexpected node type? */
else
my_friendly_abort (116);
if (decl == NULL_TREE)
{
if (current_function_decl
&& DECL_STATIC_FUNCTION_P (current_function_decl))
error ("invalid call to member function needing `this' in static member function scope");
else
error ("pointer to member function called, but not in class scope");
return error_mark_node;
}
if (TREE_CODE (TREE_TYPE (decl)) != POINTER_TYPE
&& ! TYPE_PTRMEMFUNC_P (TREE_TYPE (decl)))
{
tree binfo = lookup_base (TREE_TYPE (decl), TREE_TYPE (ctypeptr),
ba_check, NULL);
decl = build_unary_op (ADDR_EXPR, decl, 0);
decl = build_base_path (PLUS_EXPR, decl, binfo, 1);
}
else
decl = build_c_cast (ctypeptr, decl);
params = tree_cons (NULL_TREE, decl, params);
}
return build_function_call (function, params);
}
/* Resolve a pointer to member function. INSTANCE is the object
instance to use, if the member points to a virtual member. */
tree
get_member_function_from_ptrfunc (instance_ptrptr, function)
tree *instance_ptrptr;
tree function;
{
if (TREE_CODE (function) == OFFSET_REF)
function = TREE_OPERAND (function, 1);
if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
{
tree fntype, idx, e1, delta, delta2, e2, e3, vtbl;
tree instance, basetype;
tree instance_ptr = *instance_ptrptr;
if (instance_ptr == error_mark_node
&& TREE_CODE (function) == PTRMEM_CST)
{
/* Extracting the function address from a pmf is only
allowed with -Wno-pmf-conversions. It only works for
pmf constants. */
e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
e1 = convert (TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function)), e1);
return e1;
}
if (TREE_SIDE_EFFECTS (instance_ptr))
instance_ptr = save_expr (instance_ptr);
if (TREE_SIDE_EFFECTS (function))
function = save_expr (function);
fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
/* Convert down to the right base, before using the instance. */
instance = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)), basetype,
ba_check, NULL);
instance = build_base_path (PLUS_EXPR, instance_ptr, instance, 1);
if (instance == error_mark_node && instance_ptr != error_mark_node)
return instance;
e3 = PFN_FROM_PTRMEMFUNC (function);
vtbl = build1 (NOP_EXPR, build_pointer_type (ptr_type_node), instance);
TREE_CONSTANT (vtbl) = TREE_CONSTANT (instance);
delta = cp_convert (ptrdiff_type_node,
build_component_ref (function, delta_identifier,
NULL_TREE, 0));
/* This used to avoid checking for virtual functions if basetype
has no virtual functions, according to an earlier ANSI draft.
With the final ISO C++ rules, such an optimization is
incorrect: A pointer to a derived member can be static_cast
to pointer-to-base-member, as long as the dynamic object
later has the right member. */
/* Promoting idx before saving it improves performance on RISC
targets. Without promoting, the first compare used
load-with-sign-extend, while the second used normal load then
shift to sign-extend. An optimizer flaw, perhaps, but it's
easier to make this change. */
switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
{
case ptrmemfunc_vbit_in_pfn:
idx = cp_build_binary_op (TRUNC_DIV_EXPR,
build1 (NOP_EXPR, vtable_index_type, e3),
TYPE_SIZE_UNIT (vtable_entry_type));
e1 = cp_build_binary_op (BIT_AND_EXPR,
build1 (NOP_EXPR, vtable_index_type, e3),
integer_one_node);
break;
case ptrmemfunc_vbit_in_delta:
idx = build1 (NOP_EXPR, vtable_index_type, e3);
e1 = cp_build_binary_op (BIT_AND_EXPR,
delta, integer_one_node);
delta = cp_build_binary_op (RSHIFT_EXPR,
build1 (NOP_EXPR, vtable_index_type,
delta),
integer_one_node);
break;
default:
abort ();
}
/* DELTA2 is the amount by which to adjust the `this' pointer
to find the vtbl. */
delta2 = delta;
vtbl = build
(PLUS_EXPR,
build_pointer_type (build_pointer_type (vtable_entry_type)),
vtbl, cp_convert (ptrdiff_type_node, delta2));
vtbl = build_indirect_ref (vtbl, NULL);
e2 = build_array_ref (vtbl, idx);
/* When using function descriptors, the address of the
vtable entry is treated as a function pointer. */
if (TARGET_VTABLE_USES_DESCRIPTORS)
e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1));
TREE_TYPE (e2) = TREE_TYPE (e3);
e1 = build_conditional_expr (e1, e2, e3);
/* Make sure this doesn't get evaluated first inside one of the
branches of the COND_EXPR. */
if (TREE_CODE (instance_ptr) == SAVE_EXPR)
e1 = build (COMPOUND_EXPR, TREE_TYPE (e1),
instance_ptr, e1);
*instance_ptrptr = build (PLUS_EXPR, TREE_TYPE (instance_ptr),
instance_ptr, delta);
if (instance_ptr == error_mark_node
&& TREE_CODE (e1) != ADDR_EXPR
&& TREE_CODE (TREE_OPERAND (e1, 0)) != FUNCTION_DECL)
error ("object missing in `%E'", function);
function = e1;
}
return function;
}
tree
build_function_call_real (function, params, require_complete, flags)
tree function, params;
int require_complete, flags;
{
register tree fntype, fndecl;
register tree value_type;
register tree coerced_params;
tree result;
tree name = NULL_TREE, assembler_name = NULL_TREE;
int is_method;
tree original = function;
/* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
if (TREE_CODE (function) == NOP_EXPR
&& TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
function = TREE_OPERAND (function, 0);
if (TREE_CODE (function) == FUNCTION_DECL)
{
name = DECL_NAME (function);
assembler_name = DECL_ASSEMBLER_NAME (function);
GNU_xref_call (current_function_decl,
IDENTIFIER_POINTER (name ? name
: TYPE_IDENTIFIER (DECL_CLASS_CONTEXT
(function))));
mark_used (function);
fndecl = function;
/* Convert anything with function type to a pointer-to-function. */
if (pedantic && DECL_MAIN_P (function))
pedwarn ("ISO C++ forbids calling `::main' from within program");
/* Differs from default_conversion by not setting TREE_ADDRESSABLE
(because calling an inline function does not mean the function
needs to be separately compiled). */
if (DECL_INLINE (function))
function = inline_conversion (function);
else
function = build_addr_func (function);
}
else
{
fndecl = NULL_TREE;
function = build_addr_func (function);
}
if (function == error_mark_node)
return error_mark_node;
fntype = TREE_TYPE (function);
if (TYPE_PTRMEMFUNC_P (fntype))
{
error ("must use .* or ->* to call pointer-to-member function in `%E (...)'",
original);
return error_mark_node;
}
is_method = (TREE_CODE (fntype) == POINTER_TYPE
&& TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
if (!((TREE_CODE (fntype) == POINTER_TYPE
&& TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
|| is_method
|| TREE_CODE (function) == TEMPLATE_ID_EXPR))
{
error ("`%E' cannot be used as a function", original);
return error_mark_node;
}
/* fntype now gets the type of function pointed to. */
fntype = TREE_TYPE (fntype);
/* Convert the parameters to the types declared in the
function prototype, or apply default promotions. */
if (flags & LOOKUP_COMPLAIN)
coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
params, fndecl, LOOKUP_NORMAL);
else
coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
params, fndecl, 0);
if (coerced_params == error_mark_node)
{
if (flags & LOOKUP_SPECULATIVELY)
return NULL_TREE;
else
return error_mark_node;
}
/* Check for errors in format strings. */
if (warn_format)
check_function_format (NULL, TYPE_ATTRIBUTES (fntype), coerced_params);
/* Recognize certain built-in functions so we can make tree-codes
other than CALL_EXPR. We do this when it enables fold-const.c
to do something useful. */
if (TREE_CODE (function) == ADDR_EXPR
&& TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
&& DECL_BUILT_IN (TREE_OPERAND (function, 0)))
{
result = expand_tree_builtin (TREE_OPERAND (function, 0),
params, coerced_params);
if (result)
return result;
}
/* Some built-in function calls will be evaluated at
compile-time in fold (). */
result = fold (build_call (function, coerced_params));
value_type = TREE_TYPE (result);
if (require_complete)
{
if (TREE_CODE (value_type) == VOID_TYPE)
return result;
result = require_complete_type (result);
}
if (IS_AGGR_TYPE (value_type))
result = build_cplus_new (value_type, result);
return convert_from_reference (result);
}
tree
build_function_call (function, params)
tree function, params;
{
return build_function_call_real (function, params, 1, LOOKUP_NORMAL);
}
/* Convert the actual parameter expressions in the list VALUES
to the types in the list TYPELIST.
If parmdecls is exhausted, or when an element has NULL as its type,
perform the default conversions.
NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
This is also where warnings about wrong number of args are generated.
Return a list of expressions for the parameters as converted.
Both VALUES and the returned value are chains of TREE_LIST nodes
with the elements of the list in the TREE_VALUE slots of those nodes.
In C++, unspecified trailing parameters can be filled in with their
default arguments, if such were specified. Do so here. */
tree
convert_arguments (typelist, values, fndecl, flags)
tree typelist, values, fndecl;
int flags;
{
register tree typetail, valtail;
register tree result = NULL_TREE;
const char *called_thing = 0;
int i = 0;
/* Argument passing is always copy-initialization. */
flags |= LOOKUP_ONLYCONVERTING;
if (fndecl)
{
if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
{
if (DECL_NAME (fndecl) == NULL_TREE
|| IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
called_thing = "constructor";
else
called_thing = "member function";
}
else
called_thing = "function";
}
for (valtail = values, typetail = typelist;
valtail;
valtail = TREE_CHAIN (valtail), i++)
{
register tree type = typetail ? TREE_VALUE (typetail) : 0;
register tree val = TREE_VALUE (valtail);
if (val == error_mark_node)
return error_mark_node;
if (type == void_type_node)
{
if (fndecl)
{
cp_error_at ("too many arguments to %s `%+#D'", called_thing,
fndecl);
error ("at this point in file");
}
else
error ("too many arguments to function");
/* In case anybody wants to know if this argument
list is valid. */
if (result)
TREE_TYPE (tree_last (result)) = error_mark_node;
break;
}
if (TREE_CODE (val) == OFFSET_REF)
val = resolve_offset_ref (val);
/* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
if (TREE_CODE (val) == NOP_EXPR
&& TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
&& (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
val = TREE_OPERAND (val, 0);
if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
{
if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
|| TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
|| TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
val = default_conversion (val);
}
if (val == error_mark_node)
return error_mark_node;
if (type != 0)
{
/* Formal parm type is specified by a function prototype. */
tree parmval;
if (!COMPLETE_TYPE_P (complete_type (type)))
{
error ("parameter type of called function is incomplete");
parmval = val;
}
else
{
parmval = convert_for_initialization
(NULL_TREE, type, val, flags,
"argument passing", fndecl, i);
if (PROMOTE_PROTOTYPES
&& INTEGRAL_TYPE_P (type)
&& (TYPE_PRECISION (type)
< TYPE_PRECISION (integer_type_node)))
parmval = default_conversion (parmval);
}
if (parmval == error_mark_node)
return error_mark_node;
result = tree_cons (NULL_TREE, parmval, result);
}
else
{
if (TREE_CODE (TREE_TYPE (val)) == REFERENCE_TYPE)
val = convert_from_reference (val);
if (fndecl && DECL_BUILT_IN (fndecl)
&& DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
/* Don't do ellipsis conversion for __built_in_constant_p
as this will result in spurious warnings for non-POD
types. */
val = require_complete_type (val);
else
val = convert_arg_to_ellipsis (val);
result = tree_cons (NULL_TREE, val, result);
}
if (typetail)
typetail = TREE_CHAIN (typetail);
}
if (typetail != 0 && typetail != void_list_node)
{
/* See if there are default arguments that can be used */
if (TREE_PURPOSE (typetail))
{
for (; typetail != void_list_node; ++i)
{
tree parmval
= convert_default_arg (TREE_VALUE (typetail),
TREE_PURPOSE (typetail),
fndecl, i);
if (parmval == error_mark_node)
return error_mark_node;
result = tree_cons (0, parmval, result);
typetail = TREE_CHAIN (typetail);
/* ends with `...'. */
if (typetail == NULL_TREE)
break;
}
}
else
{
if (fndecl)
{
cp_error_at ("too few arguments to %s `%+#D'",
called_thing, fndecl);
error ("at this point in file");
}
else
error ("too few arguments to function");
return error_mark_list;
}
}
return nreverse (result);
}
/* Build a binary-operation expression, after performing default
conversions on the operands. CODE is the kind of expression to build. */
tree
build_x_binary_op (code, arg1, arg2)
enum tree_code code;
tree arg1, arg2;
{
if (processing_template_decl)
return build_min_nt (code, arg1, arg2);
return build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE);
}
/* Build a binary-operation expression without default conversions.
CODE is the kind of expression to build.
This function differs from `build' in several ways:
the data type of the result is computed and recorded in it,
warnings are generated if arg data types are invalid,
special handling for addition and subtraction of pointers is known,
and some optimization is done (operations on narrow ints
are done in the narrower type when that gives the same result).
Constant folding is also done before the result is returned.
Note that the operands will never have enumeral types
because either they have just had the default conversions performed
or they have both just been converted to some other type in which
the arithmetic is to be done.
C++: must do special pointer arithmetic when implementing
multiple inheritance, and deal with pointer to member functions. */
tree
build_binary_op (code, orig_op0, orig_op1, convert_p)
enum tree_code code;
tree orig_op0, orig_op1;
int convert_p ATTRIBUTE_UNUSED;
{
tree op0, op1;
register enum tree_code code0, code1;
tree type0, type1;
/* Expression code to give to the expression when it is built.
Normally this is CODE, which is what the caller asked for,
but in some special cases we change it. */
register enum tree_code resultcode = code;
/* Data type in which the computation is to be performed.
In the simplest cases this is the common type of the arguments. */
register tree result_type = NULL;
/* Nonzero means operands have already been type-converted
in whatever way is necessary.
Zero means they need to be converted to RESULT_TYPE. */
int converted = 0;
/* Nonzero means create the expression with this type, rather than
RESULT_TYPE. */
tree build_type = 0;
/* Nonzero means after finally constructing the expression
convert it to this type. */
tree final_type = 0;
/* Nonzero if this is an operation like MIN or MAX which can
safely be computed in short if both args are promoted shorts.
Also implies COMMON.
-1 indicates a bitwise operation; this makes a difference
in the exact conditions for when it is safe to do the operation
in a narrower mode. */
int shorten = 0;
/* Nonzero if this is a comparison operation;
if both args are promoted shorts, compare the original shorts.
Also implies COMMON. */
int short_compare = 0;
/* Nonzero if this is a right-shift operation, which can be computed on the
original short and then promoted if the operand is a promoted short. */
int short_shift = 0;
/* Nonzero means set RESULT_TYPE to the common type of the args. */
int common = 0;
/* Apply default conversions. */
op0 = orig_op0;
op1 = orig_op1;
if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
|| code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
|| code == TRUTH_XOR_EXPR)
{
if (!really_overloaded_fn (op0))
op0 = decay_conversion (op0);
if (!really_overloaded_fn (op1))
op1 = decay_conversion (op1);
}
else
{
if (!really_overloaded_fn (op0))
op0 = default_conversion (op0);
if (!really_overloaded_fn (op1))
op1 = default_conversion (op1);
}
/* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
STRIP_TYPE_NOPS (op0);
STRIP_TYPE_NOPS (op1);
/* DTRT if one side is an overloaded function, but complain about it. */
if (type_unknown_p (op0))
{
tree t = instantiate_type (TREE_TYPE (op1), op0, itf_none);
if (t != error_mark_node)
{
pedwarn ("assuming cast to type `%T' from overloaded function",
TREE_TYPE (t));
op0 = t;
}
}
if (type_unknown_p (op1))
{
tree t = instantiate_type (TREE_TYPE (op0), op1, itf_none);
if (t != error_mark_node)
{
pedwarn ("assuming cast to type `%T' from overloaded function",
TREE_TYPE (t));
op1 = t;
}
}
type0 = TREE_TYPE (op0);
type1 = TREE_TYPE (op1);
/* The expression codes of the data types of the arguments tell us
whether the arguments are integers, floating, pointers, etc. */
code0 = TREE_CODE (type0);
code1 = TREE_CODE (type1);
/* If an error was already reported for one of the arguments,
avoid reporting another error. */
if (code0 == ERROR_MARK || code1 == ERROR_MARK)
return error_mark_node;
switch (code)
{
case PLUS_EXPR:
/* Handle the pointer + int case. */
if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
return pointer_int_sum (PLUS_EXPR, op0, op1);
else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
return pointer_int_sum (PLUS_EXPR, op1, op0);
else
common = 1;
break;
case MINUS_EXPR:
/* Subtraction of two similar pointers.
We must subtract them as integers, then divide by object size. */
if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
&& comp_target_types (type0, type1, 1))
return pointer_diff (op0, op1, common_type (type0, type1));
/* Handle pointer minus int. Just like pointer plus int. */
else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
return pointer_int_sum (MINUS_EXPR, op0, op1);
else
common = 1;
break;
case MULT_EXPR:
common = 1;
break;
case TRUNC_DIV_EXPR:
case CEIL_DIV_EXPR:
case FLOOR_DIV_EXPR:
case ROUND_DIV_EXPR:
case EXACT_DIV_EXPR:
if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
|| code0 == COMPLEX_TYPE)
&& (code1 == INTEGER_TYPE || code1 == REAL_TYPE
|| code1 == COMPLEX_TYPE))
{
if (TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1))
warning ("division by zero in `%E / 0'", op0);
else if (TREE_CODE (op1) == REAL_CST && real_zerop (op1))
warning ("division by zero in `%E / 0.'", op0);
if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
resultcode = RDIV_EXPR;
else
/* When dividing two signed integers, we have to promote to int.
unless we divide by a constant != -1. Note that default
conversion will have been performed on the operands at this
point, so we have to dig out the original type to find out if
it was unsigned. */
shorten = ((TREE_CODE (op0) == NOP_EXPR
&& TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
|| (TREE_CODE (op1) == INTEGER_CST
&& ! integer_all_onesp (op1)));
common = 1;
}
break;
case BIT_AND_EXPR:
case BIT_ANDTC_EXPR:
case BIT_IOR_EXPR:
case BIT_XOR_EXPR:
if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
shorten = -1;
/* If one operand is a constant, and the other is a short type
that has been converted to an int,
really do the work in the short type and then convert the
result to int. If we are lucky, the constant will be 0 or 1
in the short type, making the entire operation go away. */
if (TREE_CODE (op0) == INTEGER_CST
&& TREE_CODE (op1) == NOP_EXPR
&& (TYPE_PRECISION (type1)
> TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0))))
&& TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op1, 0))))
{
final_type = result_type;
op1 = TREE_OPERAND (op1, 0);
result_type = TREE_TYPE (op1);
}
if (TREE_CODE (op1) == INTEGER_CST
&& TREE_CODE (op0) == NOP_EXPR
&& (TYPE_PRECISION (type0)
> TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0))))
&& TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
{
final_type = result_type;
op0 = TREE_OPERAND (op0, 0);
result_type = TREE_TYPE (op0);
}
break;
case TRUNC_MOD_EXPR:
case FLOOR_MOD_EXPR:
if (code1 == INTEGER_TYPE && integer_zerop (op1))
warning ("division by zero in `%E %% 0'", op0);
else if (code1 == REAL_TYPE && real_zerop (op1))
warning ("division by zero in `%E %% 0.'", op0);
if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
{
/* Although it would be tempting to shorten always here, that loses
on some targets, since the modulo instruction is undefined if the
quotient can't be represented in the computation mode. We shorten
only if unsigned or if dividing by something we know != -1. */
shorten = ((TREE_CODE (op0) == NOP_EXPR
&& TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
|| (TREE_CODE (op1) == INTEGER_CST
&& ! integer_all_onesp (op1)));
common = 1;
}
break;
case TRUTH_ANDIF_EXPR:
case TRUTH_ORIF_EXPR:
case TRUTH_AND_EXPR:
case TRUTH_OR_EXPR:
result_type = boolean_type_node;
break;
/* Shift operations: result has same type as first operand;
always convert second operand to int.
Also set SHORT_SHIFT if shifting rightward. */
case RSHIFT_EXPR:
if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
{
result_type = type0;
if (TREE_CODE (op1) == INTEGER_CST)
{
if (tree_int_cst_lt (op1, integer_zero_node))
warning ("right shift count is negative");
else
{
if (! integer_zerop (op1))
short_shift = 1;
if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
warning ("right shift count >= width of type");
}
}
/* Convert the shift-count to an integer, regardless of
size of value being shifted. */
if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
op1 = cp_convert (integer_type_node, op1);
/* Avoid converting op1 to result_type later. */
converted = 1;
}
break;
case LSHIFT_EXPR:
if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
{
result_type = type0;
if (TREE_CODE (op1) == INTEGER_CST)
{
if (tree_int_cst_lt (op1, integer_zero_node))
warning ("left shift count is negative");
else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
warning ("left shift count >= width of type");
}
/* Convert the shift-count to an integer, regardless of
size of value being shifted. */
if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
op1 = cp_convert (integer_type_node, op1);
/* Avoid converting op1 to result_type later. */
converted = 1;
}
break;
case RROTATE_EXPR:
case LROTATE_EXPR:
if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
{
result_type = type0;
if (TREE_CODE (op1) == INTEGER_CST)
{
if (tree_int_cst_lt (op1, integer_zero_node))
warning ("%s rotate count is negative",
(code == LROTATE_EXPR) ? "left" : "right");
else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
warning ("%s rotate count >= width of type",
(code == LROTATE_EXPR) ? "left" : "right");
}
/* Convert the shift-count to an integer, regardless of
size of value being shifted. */
if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
op1 = cp_convert (integer_type_node, op1);
}
break;
case EQ_EXPR:
case NE_EXPR:
if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
warning ("comparing floating point with == or != is unsafe");
build_type = boolean_type_node;
if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
|| code0 == COMPLEX_TYPE)
&& (code1 == INTEGER_TYPE || code1 == REAL_TYPE
|| code1 == COMPLEX_TYPE))
short_compare = 1;
else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
result_type = composite_pointer_type (type0, type1, op0, op1,
"comparison");
else if (code0 == POINTER_TYPE && null_ptr_cst_p (op1))
result_type = type0;
else if (code1 == POINTER_TYPE && null_ptr_cst_p (op0))
result_type = type1;
else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
{
result_type = type0;
error ("ISO C++ forbids comparison between pointer and integer");
}
else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
{
result_type = type1;
error ("ISO C++ forbids comparison between pointer and integer");
}
else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
{
op0 = build_component_ref (op0, pfn_identifier, NULL_TREE, 0);
op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
result_type = TREE_TYPE (op0);
}
else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
return cp_build_binary_op (code, op1, op0);
else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)
&& same_type_p (type0, type1))
{
/* E will be the final comparison. */
tree e;
/* E1 and E2 are for scratch. */
tree e1;
tree e2;
tree pfn0;
tree pfn1;
tree delta0;
tree delta1;
if (TREE_SIDE_EFFECTS (op0))
op0 = save_expr (op0);
if (TREE_SIDE_EFFECTS (op1))
op1 = save_expr (op1);
/* We generate:
(op0.pfn == op1.pfn
&& (!op0.pfn || op0.delta == op1.delta))
The reason for the `!op0.pfn' bit is that a NULL
pointer-to-member is any member with a zero PFN; the
DELTA field is unspecified. */
pfn0 = pfn_from_ptrmemfunc (op0);
pfn1 = pfn_from_ptrmemfunc (op1);
delta0 = build_component_ref (op0, delta_identifier,
NULL_TREE, 0);
delta1 = build_component_ref (op1, delta_identifier,
NULL_TREE, 0);
e1 = cp_build_binary_op (EQ_EXPR, delta0, delta1);
e2 = cp_build_binary_op (EQ_EXPR,
pfn0,
cp_convert (TREE_TYPE (pfn0),
integer_zero_node));
e1 = cp_build_binary_op (TRUTH_ORIF_EXPR, e1, e2);
e2 = build (EQ_EXPR, boolean_type_node, pfn0, pfn1);
e = cp_build_binary_op (TRUTH_ANDIF_EXPR, e2, e1);
if (code == EQ_EXPR)
return e;
return cp_build_binary_op (EQ_EXPR, e, integer_zero_node);
}
else if ((TYPE_PTRMEMFUNC_P (type0)
&& same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0), type1))
|| (TYPE_PTRMEMFUNC_P (type1)
&& same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1), type0)))
my_friendly_abort (20000221);
break;
case MAX_EXPR:
case MIN_EXPR:
if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
&& (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
shorten = 1;
else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
result_type = composite_pointer_type (type0, type1, op0, op1,
"comparison");
break;
case LE_EXPR:
case GE_EXPR:
case LT_EXPR:
case GT_EXPR:
build_type = boolean_type_node;
if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
&& (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
short_compare = 1;
else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
result_type = composite_pointer_type (type0, type1, op0, op1,
"comparison");
else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
&& integer_zerop (op1))
result_type = type0;
else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
&& integer_zerop (op0))
result_type = type1;
else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
{
result_type = type0;
pedwarn ("ISO C++ forbids comparison between pointer and integer");
}
else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
{
result_type = type1;
pedwarn ("ISO C++ forbids comparison between pointer and integer");
}
break;
case UNORDERED_EXPR:
case ORDERED_EXPR:
case UNLT_EXPR:
case UNLE_EXPR:
case UNGT_EXPR:
case UNGE_EXPR:
case UNEQ_EXPR:
build_type = integer_type_node;
if (code0 != REAL_TYPE || code1 != REAL_TYPE)
{
error ("unordered comparison on non-floating point argument");
return error_mark_node;
}
common = 1;
break;
default:
break;
}
if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
&&
(code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
{
int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
if (shorten || common || short_compare)
result_type = common_type (type0, type1);
/* For certain operations (which identify themselves by shorten != 0)
if both args were extended from the same smaller type,
do the arithmetic in that type and then extend.
shorten !=0 and !=1 indicates a bitwise operation.
For them, this optimization is safe only if
both args are zero-extended or both are sign-extended.
Otherwise, we might change the result.
Eg, (short)-1 | (unsigned short)-1 is (int)-1
but calculated in (unsigned short) it would be (unsigned short)-1. */
if (shorten && none_complex)
{
int unsigned0, unsigned1;
tree arg0 = get_narrower (op0, &unsigned0);
tree arg1 = get_narrower (op1, &unsigned1);
/* UNS is 1 if the operation to be done is an unsigned one. */
int uns = TREE_UNSIGNED (result_type);
tree type;
final_type = result_type;
/* Handle the case that OP0 does not *contain* a conversion
but it *requires* conversion to FINAL_TYPE. */
if (op0 == arg0 && TREE_TYPE (op0) != final_type)
unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0));
if (op1 == arg1 && TREE_TYPE (op1) != final_type)
unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1));
/* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
/* For bitwise operations, signedness of nominal type
does not matter. Consider only how operands were extended. */
if (shorten == -1)
uns = unsigned0;
/* Note that in all three cases below we refrain from optimizing
an unsigned operation on sign-extended args.
That would not be valid. */
/* Both args variable: if both extended in same way
from same width, do it in that width.
Do it unsigned if args were zero-extended. */
if ((TYPE_PRECISION (TREE_TYPE (arg0))
< TYPE_PRECISION (result_type))
&& (TYPE_PRECISION (TREE_TYPE (arg1))
== TYPE_PRECISION (TREE_TYPE (arg0)))
&& unsigned0 == unsigned1
&& (unsigned0 || !uns))
result_type
= signed_or_unsigned_type (unsigned0,
common_type (TREE_TYPE (arg0),
TREE_TYPE (arg1)));
else if (TREE_CODE (arg0) == INTEGER_CST
&& (unsigned1 || !uns)
&& (TYPE_PRECISION (TREE_TYPE (arg1))
< TYPE_PRECISION (result_type))
&& (type = signed_or_unsigned_type (unsigned1,
TREE_TYPE (arg1)),
int_fits_type_p (arg0, type)))
result_type = type;
else if (TREE_CODE (arg1) == INTEGER_CST
&& (unsigned0 || !uns)
&& (TYPE_PRECISION (TREE_TYPE (arg0))
< TYPE_PRECISION (result_type))
&& (type = signed_or_unsigned_type (unsigned0,
TREE_TYPE (arg0)),
int_fits_type_p (arg1, type)))
result_type = type;
}
/* Shifts can be shortened if shifting right. */
if (short_shift)
{
int unsigned_arg;
tree arg0 = get_narrower (op0, &unsigned_arg);
final_type = result_type;
if (arg0 == op0 && final_type == TREE_TYPE (op0))
unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0));
if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
/* We can shorten only if the shift count is less than the
number of bits in the smaller type size. */
&& compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
/* If arg is sign-extended and then unsigned-shifted,
we can simulate this with a signed shift in arg's type
only if the extended result is at least twice as wide
as the arg. Otherwise, the shift could use up all the
ones made by sign-extension and bring in zeros.
We can't optimize that case at all, but in most machines
it never happens because available widths are 2**N. */
&& (!TREE_UNSIGNED (final_type)
|| unsigned_arg
|| (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0)))
<= TYPE_PRECISION (result_type))))
{
/* Do an unsigned shift if the operand was zero-extended. */
result_type
= signed_or_unsigned_type (unsigned_arg,
TREE_TYPE (arg0));
/* Convert value-to-be-shifted to that type. */
if (TREE_TYPE (op0) != result_type)
op0 = cp_convert (result_type, op0);
converted = 1;
}
}
/* Comparison operations are shortened too but differently.
They identify themselves by setting short_compare = 1. */
if (short_compare)
{
/* Don't write &op0, etc., because that would prevent op0
from being kept in a register.
Instead, make copies of the our local variables and
pass the copies by reference, then copy them back afterward. */
tree xop0 = op0, xop1 = op1, xresult_type = result_type;
enum tree_code xresultcode = resultcode;
tree val
= shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
if (val != 0)
return cp_convert (boolean_type_node, val);
op0 = xop0, op1 = xop1;
converted = 1;
resultcode = xresultcode;
}
if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
&& warn_sign_compare)
{
int op0_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op0));
int op1_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op1));
int unsignedp0, unsignedp1;
tree primop0 = get_narrower (op0, &unsignedp0);
tree primop1 = get_narrower (op1, &unsignedp1);
/* Check for comparison of different enum types. */
if (TREE_CODE (TREE_TYPE (orig_op0)) == ENUMERAL_TYPE
&& TREE_CODE (TREE_TYPE (orig_op1)) == ENUMERAL_TYPE
&& TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0))
!= TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1)))
{
warning ("comparison between types `%#T' and `%#T'",
TREE_TYPE (orig_op0), TREE_TYPE (orig_op1));
}
/* Give warnings for comparisons between signed and unsigned
quantities that may fail. */
/* Do the checking based on the original operand trees, so that
casts will be considered, but default promotions won't be. */
/* Do not warn if the comparison is being done in a signed type,
since the signed type will only be chosen if it can represent
all the values of the unsigned type. */
if (! TREE_UNSIGNED (result_type))
/* OK */;
/* Do not warn if both operands are unsigned. */
else if (op0_signed == op1_signed)
/* OK */;
/* Do not warn if the signed quantity is an unsuffixed
integer literal (or some static constant expression
involving such literals or a conditional expression
involving such literals) and it is non-negative. */
else if ((op0_signed && tree_expr_nonnegative_p (orig_op0))
|| (op1_signed && tree_expr_nonnegative_p (orig_op1)))
/* OK */;
/* Do not warn if the comparison is an equality operation,
the unsigned quantity is an integral constant and it does
not use the most significant bit of result_type. */
else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
&& ((op0_signed && TREE_CODE (orig_op1) == INTEGER_CST
&& int_fits_type_p (orig_op1,
signed_type (result_type)))
|| (op1_signed && TREE_CODE (orig_op0) == INTEGER_CST
&& int_fits_type_p (orig_op0,
signed_type (result_type)))))
/* OK */;
else
warning ("comparison between signed and unsigned integer expressions");
/* Warn if two unsigned values are being compared in a size
larger than their original size, and one (and only one) is the
result of a `~' operator. This comparison will always fail.
Also warn if one operand is a constant, and the constant does not
have all bits set that are set in the ~ operand when it is
extended. */
if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
^ (TREE_CODE (primop1) == BIT_NOT_EXPR))
{
if (TREE_CODE (primop0) == BIT_NOT_EXPR)
primop0 = get_narrower (TREE_OPERAND (op0, 0), &unsignedp0);
if (TREE_CODE (primop1) == BIT_NOT_EXPR)
primop1 = get_narrower (TREE_OPERAND (op1, 0), &unsignedp1);
if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
{
tree primop;
HOST_WIDE_INT constant, mask;
int unsignedp;
unsigned int bits;
if (host_integerp (primop0, 0))
{
primop = primop1;
unsignedp = unsignedp1;
constant = tree_low_cst (primop0, 0);
}
else
{
primop = primop0;
unsignedp = unsignedp0;
constant = tree_low_cst (primop1, 0);
}
bits = TYPE_PRECISION (TREE_TYPE (primop));
if (bits < TYPE_PRECISION (result_type)
&& bits < HOST_BITS_PER_LONG && unsignedp)
{
mask = (~ (HOST_WIDE_INT) 0) << bits;
if ((mask & constant) != mask)
warning ("comparison of promoted ~unsigned with constant");
}
}
else if (unsignedp0 && unsignedp1
&& (TYPE_PRECISION (TREE_TYPE (primop0))
< TYPE_PRECISION (result_type))
&& (TYPE_PRECISION (TREE_TYPE (primop1))
< TYPE_PRECISION (result_type)))
warning ("comparison of promoted ~unsigned with unsigned");
}
}
}
/* At this point, RESULT_TYPE must be nonzero to avoid an error message.
If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
Then the expression will be built.
It will be given type FINAL_TYPE if that is nonzero;
otherwise, it will be given type RESULT_TYPE. */
if (!result_type)
{
error ("invalid operands of types `%T' and `%T' to binary `%O'",
TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
return error_mark_node;
}
/* Issue warnings about peculiar, but legal, uses of NULL. */
if (/* It's reasonable to use pointer values as operands of &&
and ||, so NULL is no exception. */
!(code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
&& (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
(orig_op0 == null_node
&& TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE)
/* Or vice versa. */
|| (orig_op1 == null_node
&& TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
/* Or, both are NULL and the operation was not a comparison. */
|| (orig_op0 == null_node && orig_op1 == null_node
&& code != EQ_EXPR && code != NE_EXPR)))
/* Some sort of arithmetic operation involving NULL was
performed. Note that pointer-difference and pointer-addition
have already been handled above, and so we don't end up here in
that case. */
warning ("NULL used in arithmetic");
if (! converted)
{
if (TREE_TYPE (op0) != result_type)
op0 = cp_convert (result_type, op0);
if (TREE_TYPE (op1) != result_type)
op1 = cp_convert (result_type, op1);
if (op0 == error_mark_node || op1 == error_mark_node)
return error_mark_node;
}
if (build_type == NULL_TREE)
build_type = result_type;
{
register tree result = build (resultcode, build_type, op0, op1);
register tree folded;
folded = fold (result);
if (folded == result)
TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
if (final_type != 0)
return cp_convert (final_type, folded);
return folded;
}
}
/* Return a tree for the sum or difference (RESULTCODE says which)
of pointer PTROP and integer INTOP. */
static tree
pointer_int_sum (resultcode, ptrop, intop)
enum tree_code resultcode;
register tree ptrop, intop;
{
tree size_exp;
register tree result;
register tree folded = fold (intop);
/* The result is a pointer of the same type that is being added. */
register tree result_type = TREE_TYPE (ptrop);
if (!complete_type_or_else (result_type, ptrop))
return error_mark_node;
if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)
{
if (pedantic || warn_pointer_arith)
pedwarn ("ISO C++ forbids using pointer of type `void *' in pointer arithmetic");
size_exp = integer_one_node;
}
else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE)
{
if (pedantic || warn_pointer_arith)
pedwarn ("ISO C++ forbids using a pointer-to-function in pointer arithmetic");
size_exp = integer_one_node;
}
else if (TREE_CODE (TREE_TYPE (result_type)) == METHOD_TYPE)
{
if (pedantic || warn_pointer_arith)
pedwarn ("ISO C++ forbids using a pointer to member function in pointer arithmetic");
size_exp = integer_one_node;
}
else if (TREE_CODE (TREE_TYPE (result_type)) == OFFSET_TYPE)
{
if (pedantic || warn_pointer_arith)
pedwarn ("ISO C++ forbids using pointer to a member in pointer arithmetic");
size_exp = integer_one_node;
}
else
size_exp = size_in_bytes (complete_type (TREE_TYPE (result_type)));
/* Needed to make OOPS V2R3 work. */
intop = folded;
if (integer_zerop (intop))
return ptrop;
/* If what we are about to multiply by the size of the elements
contains a constant term, apply distributive law
and multiply that constant term separately.
This helps produce common subexpressions. */
if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR)
&& ! TREE_CONSTANT (intop)
&& TREE_CONSTANT (TREE_OPERAND (intop, 1))
&& TREE_CONSTANT (size_exp))
{
enum tree_code subcode = resultcode;
if (TREE_CODE (intop) == MINUS_EXPR)
subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR);
ptrop = cp_build_binary_op (subcode, ptrop, TREE_OPERAND (intop, 1));
intop = TREE_OPERAND (intop, 0);
}
/* Convert the integer argument to a type the same size as sizetype
so the multiply won't overflow spuriously. */
if (TYPE_PRECISION (TREE_TYPE (intop)) != TYPE_PRECISION (sizetype))
intop = cp_convert (type_for_size (TYPE_PRECISION (sizetype), 0), intop);
/* Replace the integer argument with a suitable product by the object size.
Do this multiplication as signed, then convert to the appropriate
pointer type (actually unsigned integral). */
intop = cp_convert (result_type,
cp_build_binary_op (MULT_EXPR, intop,
cp_convert (TREE_TYPE (intop),
size_exp)));
/* Create the sum or difference. */
result = build (resultcode, result_type, ptrop, intop);
folded = fold (result);
if (folded == result)
TREE_CONSTANT (folded) = TREE_CONSTANT (ptrop) & TREE_CONSTANT (intop);
return folded;
}
/* Return a tree for the difference of pointers OP0 and OP1.
The resulting tree has type int. */
static tree
pointer_diff (op0, op1, ptrtype)
register tree op0, op1;
register tree ptrtype;
{
register tree result, folded;
tree restype = ptrdiff_type_node;
tree target_type = TREE_TYPE (ptrtype);
if (!complete_type_or_else (target_type, NULL_TREE))
return error_mark_node;
if (pedantic || warn_pointer_arith)
{
if (TREE_CODE (target_type) == VOID_TYPE)
pedwarn ("ISO C++ forbids using pointer of type `void *' in subtraction");
if (TREE_CODE (target_type) == FUNCTION_TYPE)
pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
if (TREE_CODE (target_type) == METHOD_TYPE)
pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
if (TREE_CODE (target_type) == OFFSET_TYPE)
pedwarn ("ISO C++ forbids using pointer to a member in subtraction");
}
/* First do the subtraction as integers;
then drop through to build the divide operator. */
op0 = cp_build_binary_op (MINUS_EXPR,
cp_convert (restype, op0),
cp_convert (restype, op1));
/* This generates an error if op1 is a pointer to an incomplete type. */
if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
op1 = ((TREE_CODE (target_type) == VOID_TYPE
|| TREE_CODE (target_type) == FUNCTION_TYPE
|| TREE_CODE (target_type) == METHOD_TYPE
|| TREE_CODE (target_type) == OFFSET_TYPE)
? integer_one_node
: size_in_bytes (target_type));
/* Do the division. */
result = build (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
folded = fold (result);
if (folded == result)
TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
return folded;
}
/* Handle the case of taking the address of a COMPONENT_REF.
Called by `build_unary_op'.
ARG is the COMPONENT_REF whose address we want.
ARGTYPE is the pointer type that this address should have. */
static tree
build_component_addr (arg, argtype)
tree arg, argtype;
{
tree field = TREE_OPERAND (arg, 1);
tree basetype = decl_type_context (field);
tree rval = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0);
my_friendly_assert (TREE_CODE (field) == FIELD_DECL, 981018);
if (DECL_C_BIT_FIELD (field))
{
error ("attempt to take address of bit-field structure member `%D'",
field);
return error_mark_node;
}
if (TREE_CODE (field) == FIELD_DECL
&& TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (basetype))
{
/* Can't convert directly to ARGTYPE, since that
may have the same pointer type as one of our
baseclasses. */
tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (rval)), basetype,
ba_check, NULL);
rval = build_base_path (PLUS_EXPR, rval, binfo, 1);
rval = build1 (NOP_EXPR, argtype, rval);
TREE_CONSTANT (rval) = TREE_CONSTANT (TREE_OPERAND (rval, 0));
}
else
/* This conversion is harmless. */
rval = convert_force (argtype, rval, 0);
return fold (build (PLUS_EXPR, argtype, rval,
cp_convert (argtype, byte_position (field))));
}
/* Construct and perhaps optimize a tree representation
for a unary operation. CODE, a tree_code, specifies the operation
and XARG is the operand. */
tree
build_x_unary_op (code, xarg)
enum tree_code code;
tree xarg;
{
tree exp;
int ptrmem = 0;
if (processing_template_decl)
return build_min_nt (code, xarg, NULL_TREE);
/* & rec, on incomplete RECORD_TYPEs is the simple opr &, not an
error message. */
if (code == ADDR_EXPR
&& TREE_CODE (xarg) != TEMPLATE_ID_EXPR
&& ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (xarg)))
&& !COMPLETE_TYPE_P (TREE_TYPE (xarg)))
|| (TREE_CODE (xarg) == OFFSET_REF)))
/* don't look for a function */;
else
{
tree rval;
rval = build_new_op (code, LOOKUP_NORMAL, xarg,
NULL_TREE, NULL_TREE);
if (rval || code != ADDR_EXPR)
return rval;
}
if (code == ADDR_EXPR)
{
if (TREE_CODE (xarg) == OFFSET_REF)
{
ptrmem = PTRMEM_OK_P (xarg);
if (!ptrmem && !flag_ms_extensions
&& TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
/* A single non-static member, make sure we don't allow a
pointer-to-member. */
xarg = ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE);
}
else if (TREE_CODE (xarg) == TARGET_EXPR)
warning ("taking address of temporary");
}
exp = build_unary_op (code, xarg, 0);
if (TREE_CODE (exp) == ADDR_EXPR)
PTRMEM_OK_P (exp) = ptrmem;
return exp;
}
/* Like truthvalue_conversion, but handle pointer-to-member constants, where
a null value is represented by an INTEGER_CST of -1. */
tree
cp_truthvalue_conversion (expr)
tree expr;
{
tree type = TREE_TYPE (expr);
if (TYPE_PTRMEM_P (type))
return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
else
return truthvalue_conversion (expr);
}
/* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
tree
condition_conversion (expr)
tree expr;
{
tree t;
if (processing_template_decl)
return expr;
if (TREE_CODE (expr) == OFFSET_REF)
expr = resolve_offset_ref (expr);
t = perform_implicit_conversion (boolean_type_node, expr);
t = fold (build1 (CLEANUP_POINT_EXPR, boolean_type_node, t));
return t;
}
/* C++: Must handle pointers to members.
Perhaps type instantiation should be extended to handle conversion
from aggregates to types we don't yet know we want? (Or are those
cases typically errors which should be reported?)
NOCONVERT nonzero suppresses the default promotions
(such as from short to int). */
tree
build_unary_op (code, xarg, noconvert)
enum tree_code code;
tree xarg;
int noconvert;
{
/* No default_conversion here. It causes trouble for ADDR_EXPR. */
register tree arg = xarg;
register tree argtype = 0;
const char *errstring = NULL;
tree val;
if (arg == error_mark_node)
return error_mark_node;
switch (code)
{
case CONVERT_EXPR:
/* This is used for unary plus, because a CONVERT_EXPR
is enough to prevent anybody from looking inside for
associativity, but won't generate any code. */
if (!(arg = build_expr_type_conversion
(WANT_ARITH | WANT_ENUM | WANT_POINTER, arg, 1)))
errstring = "wrong type argument to unary plus";
else
{
if (!noconvert)
arg = default_conversion (arg);
arg = build1 (NON_LVALUE_EXPR, TREE_TYPE (arg), arg);
TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
}
break;
case NEGATE_EXPR:
if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, 1)))
errstring = "wrong type argument to unary minus";
else if (!noconvert)
arg = default_conversion (arg);
break;
case BIT_NOT_EXPR:
if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
{
code = CONJ_EXPR;
if (!noconvert)
arg = default_conversion (arg);
}
else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM,
arg, 1)))
errstring = "wrong type argument to bit-complement";
else if (!noconvert)
arg = default_conversion (arg);
break;
case ABS_EXPR:
if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, 1)))
errstring = "wrong type argument to abs";
else if (!noconvert)
arg = default_conversion (arg);
break;
case CONJ_EXPR:
/* Conjugating a real value is a no-op, but allow it anyway. */
if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, 1)))
errstring = "wrong type argument to conjugation";
else if (!noconvert)
arg = default_conversion (arg);
break;
case TRUTH_NOT_EXPR:
arg = cp_convert (boolean_type_node, arg);
val = invert_truthvalue (arg);
if (arg != error_mark_node)
return val;
errstring = "in argument to unary !";
break;
case NOP_EXPR:
break;
case REALPART_EXPR:
if (TREE_CODE (arg) == COMPLEX_CST)
return TREE_REALPART (arg);
else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
else
return arg;
case IMAGPART_EXPR:
if (TREE_CODE (arg) == COMPLEX_CST)
return TREE_IMAGPART (arg);
else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
else
return cp_convert (TREE_TYPE (arg), integer_zero_node);
case PREINCREMENT_EXPR:
case POSTINCREMENT_EXPR:
case PREDECREMENT_EXPR:
case POSTDECREMENT_EXPR:
/* Handle complex lvalues (when permitted)
by reduction to simpler cases. */
val = unary_complex_lvalue (code, arg);
if (val != 0)
return val;
/* Increment or decrement the real part of the value,
and don't change the imaginary part. */
if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
{
tree real, imag;
arg = stabilize_reference (arg);
real = build_unary_op (REALPART_EXPR, arg, 1);
imag = build_unary_op (IMAGPART_EXPR, arg, 1);
return build (COMPLEX_EXPR, TREE_TYPE (arg),
build_unary_op (code, real, 1), imag);
}
/* Report invalid types. */
if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
arg, 1)))
{
if (code == PREINCREMENT_EXPR)
errstring ="no pre-increment operator for type";
else if (code == POSTINCREMENT_EXPR)
errstring ="no post-increment operator for type";
else if (code == PREDECREMENT_EXPR)
errstring ="no pre-decrement operator for type";
else
errstring ="no post-decrement operator for type";
break;
}
/* Report something read-only. */
if (CP_TYPE_CONST_P (TREE_TYPE (arg))
|| TREE_READONLY (arg))
readonly_error (arg, ((code == PREINCREMENT_EXPR
|| code == POSTINCREMENT_EXPR)
? "increment" : "decrement"),
0);
{
register tree inc;
tree result_type = TREE_TYPE (arg);
arg = get_unwidened (arg, 0);
argtype = TREE_TYPE (arg);
/* ARM $5.2.5 last annotation says this should be forbidden. */
if (TREE_CODE (argtype) == ENUMERAL_TYPE)
pedwarn ("ISO C++ forbids %sing an enum",
(code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
? "increment" : "decrement");
/* Compute the increment. */
if (TREE_CODE (argtype) == POINTER_TYPE)
{
enum tree_code tmp = TREE_CODE (TREE_TYPE (argtype));
tree type = complete_type (TREE_TYPE (argtype));
if (!COMPLETE_OR_VOID_TYPE_P (type))
error ("cannot %s a pointer to incomplete type `%T'",
((code == PREINCREMENT_EXPR
|| code == POSTINCREMENT_EXPR)
? "increment" : "decrement"), TREE_TYPE (argtype));
else if ((pedantic || warn_pointer_arith)
&& (tmp == FUNCTION_TYPE || tmp == METHOD_TYPE
|| tmp == VOID_TYPE || tmp == OFFSET_TYPE))
pedwarn ("ISO C++ forbids %sing a pointer of type `%T'",
((code == PREINCREMENT_EXPR
|| code == POSTINCREMENT_EXPR)
? "increment" : "decrement"), argtype);
inc = c_sizeof_nowarn (TREE_TYPE (argtype));
}
else
inc = integer_one_node;
inc = cp_convert (argtype, inc);
/* Handle incrementing a cast-expression. */
switch (TREE_CODE (arg))
{
case NOP_EXPR:
case CONVERT_EXPR:
case FLOAT_EXPR:
case FIX_TRUNC_EXPR:
case FIX_FLOOR_EXPR:
case FIX_ROUND_EXPR:
case FIX_CEIL_EXPR:
{
tree incremented, modify, value, compound;
if (! lvalue_p (arg) && pedantic)
pedwarn ("cast to non-reference type used as lvalue");
arg = stabilize_reference (arg);
if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
value = arg;
else
value = save_expr (arg);
incremented = build (((code == PREINCREMENT_EXPR
|| code == POSTINCREMENT_EXPR)
? PLUS_EXPR : MINUS_EXPR),
argtype, value, inc);
modify = build_modify_expr (arg, NOP_EXPR, incremented);
compound = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value);
/* Eliminate warning about unused result of + or -. */
TREE_NO_UNUSED_WARNING (compound) = 1;
return compound;
}
default:
break;
}
/* Complain about anything else that is not a true lvalue. */
if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
|| code == POSTINCREMENT_EXPR)
? "increment" : "decrement")))
return error_mark_node;
/* Forbid using -- on `bool'. */
if (TREE_TYPE (arg) == boolean_type_node)
{
if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
{
error ("invalid use of `--' on bool variable `%D'", arg);
return error_mark_node;
}
#if 0
/* This will only work if someone can convince Kenner to accept
my patch to expand_increment. (jason) */
val = build (code, TREE_TYPE (arg), arg, inc);
#else
val = boolean_increment (code, arg);
#endif
}
else
val = build (code, TREE_TYPE (arg), arg, inc);
TREE_SIDE_EFFECTS (val) = 1;
return cp_convert (result_type, val);
}
case ADDR_EXPR:
/* Note that this operation never does default_conversion
regardless of NOCONVERT. */
argtype = lvalue_type (arg);
if (TREE_CODE (argtype) == REFERENCE_TYPE)
{
arg = build1
(CONVERT_EXPR,
build_pointer_type (TREE_TYPE (argtype)), arg);
TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
return arg;
}
else if (pedantic && DECL_MAIN_P (arg))
/* ARM $3.4 */
pedwarn ("ISO C++ forbids taking address of function `::main'");
/* Let &* cancel out to simplify resulting code. */
if (TREE_CODE (arg) == INDIRECT_REF)
{
/* We don't need to have `current_class_ptr' wrapped in a
NON_LVALUE_EXPR node. */
if (arg == current_class_ref)
return current_class_ptr;
arg = TREE_OPERAND (arg, 0);
if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
{
arg = build1
(CONVERT_EXPR,
build_pointer_type (TREE_TYPE (TREE_TYPE (arg))), arg);
TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
}
else if (lvalue_p (arg))
/* Don't let this be an lvalue. */
return non_lvalue (arg);
return arg;
}
/* For &x[y], return x+y */
if (TREE_CODE (arg) == ARRAY_REF)
{
if (mark_addressable (TREE_OPERAND (arg, 0)) == 0)
return error_mark_node;
return cp_build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
TREE_OPERAND (arg, 1));
}
/* Uninstantiated types are all functions. Taking the
address of a function is a no-op, so just return the
argument. */
if (TREE_CODE (arg) == IDENTIFIER_NODE
&& IDENTIFIER_OPNAME_P (arg))
{
my_friendly_abort (117);
/* We don't know the type yet, so just work around the problem.
We know that this will resolve to an lvalue. */
return build1 (ADDR_EXPR, unknown_type_node, arg);
}
if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
&& OVL_NEXT (TREE_OPERAND (arg, 1)) == NULL_TREE)
{
/* They're trying to take the address of a unique non-static
member function. This is ill-formed (except in MS-land),
but let's try to DTRT.
Note: We only handle unique functions here because we don't
want to complain if there's a static overload; non-unique
cases will be handled by instantiate_type. But we need to
handle this case here to allow casts on the resulting PMF.
We could defer this in non-MS mode, but it's easier to give
a useful error here. */
tree base = TREE_TYPE (TREE_OPERAND (arg, 0));
tree name = DECL_NAME (OVL_CURRENT (TREE_OPERAND (arg, 1)));
if (! flag_ms_extensions)
{
if (current_class_type
&& TREE_OPERAND (arg, 0) == current_class_ref)
/* An expression like &memfn. */
pedwarn ("ISO C++ forbids taking the address of an unqualified non-static member function to form a pointer to member function. Say `&%T::%D'", base, name);
else
pedwarn ("ISO C++ forbids taking the address of a bound member function to form a pointer to member function. Say `&%T::%D'", base, name);
}
arg = build_offset_ref (base, name);
}
if (type_unknown_p (arg))
return build1 (ADDR_EXPR, unknown_type_node, arg);
/* Handle complex lvalues (when permitted)
by reduction to simpler cases. */
val = unary_complex_lvalue (code, arg);
if (val != 0)
return val;
switch (TREE_CODE (arg))
{
case NOP_EXPR:
case CONVERT_EXPR:
case FLOAT_EXPR:
case FIX_TRUNC_EXPR:
case FIX_FLOOR_EXPR:
case FIX_ROUND_EXPR:
case FIX_CEIL_EXPR:
if (! lvalue_p (arg) && pedantic)
pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
break;
default:
break;
}
/* Allow the address of a constructor if all the elements
are constant. */
if (TREE_CODE (arg) == CONSTRUCTOR && TREE_HAS_CONSTRUCTOR (arg)
&& TREE_CONSTANT (arg))
;
/* Anything not already handled and not a true memory reference
is an error. */
else if (TREE_CODE (argtype) != FUNCTION_TYPE
&& TREE_CODE (argtype) != METHOD_TYPE
&& !lvalue_or_else (arg, "unary `&'"))
return error_mark_node;
if (argtype != error_mark_node)
argtype = build_pointer_type (argtype);
if (mark_addressable (arg) == 0)
return error_mark_node;
{
tree addr;
if (TREE_CODE (arg) == COMPONENT_REF)
addr = build_component_addr (arg, argtype);
else
addr = build1 (ADDR_EXPR, argtype, arg);
/* Address of a static or external variable or
function counts as a constant */
if (staticp (arg))
TREE_CONSTANT (addr) = 1;
if (TREE_CODE (argtype) == POINTER_TYPE
&& TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
{
build_ptrmemfunc_type (argtype);
addr = build_ptrmemfunc (argtype, addr, 0);
}
return addr;
}
default:
break;
}
if (!errstring)
{
if (argtype == 0)
argtype = TREE_TYPE (arg);
return fold (build1 (code, argtype, arg));
}
error ("%s", errstring);
return error_mark_node;
}
/* Apply unary lvalue-demanding operator CODE to the expression ARG
for certain kinds of expressions which are not really lvalues
but which we can accept as lvalues.
If ARG is not a kind of expression we can handle, return zero. */
tree
unary_complex_lvalue (code, arg)
enum tree_code code;
tree arg;
{
/* Handle (a, b) used as an "lvalue". */
if (TREE_CODE (arg) == COMPOUND_EXPR)
{
tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
return build (COMPOUND_EXPR, TREE_TYPE (real_result),
TREE_OPERAND (arg, 0), real_result);
}
/* Handle (a ? b : c) used as an "lvalue". */
if (TREE_CODE (arg) == COND_EXPR
|| TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
return rationalize_conditional_expr (code, arg);
/* Handle (a = b), (++a), and (--a) used as an "lvalue". */
if (TREE_CODE (arg) == MODIFY_EXPR
|| TREE_CODE (arg) == PREINCREMENT_EXPR
|| TREE_CODE (arg) == PREDECREMENT_EXPR)
{
tree lvalue = TREE_OPERAND (arg, 0);
if (TREE_SIDE_EFFECTS (lvalue))
{
lvalue = stabilize_reference (lvalue);
arg = build (TREE_CODE (arg), TREE_TYPE (arg),
lvalue, TREE_OPERAND (arg, 1));
}
return unary_complex_lvalue
(code, build (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
}
if (code != ADDR_EXPR)
return 0;
/* Handle (a = b) used as an "lvalue" for `&'. */
if (TREE_CODE (arg) == MODIFY_EXPR
|| TREE_CODE (arg) == INIT_EXPR)
{
tree real_result = build_unary_op (code, TREE_OPERAND (arg, 0), 0);
arg = build (COMPOUND_EXPR, TREE_TYPE (real_result), arg, real_result);
TREE_NO_UNUSED_WARNING (arg) = 1;
return arg;
}
if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
|| TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
|| TREE_CODE (TREE_TYPE (arg)) == OFFSET_TYPE)
{
/* The representation of something of type OFFSET_TYPE
is really the representation of a pointer to it.
Here give the representation its true type. */
tree t;
my_friendly_assert (TREE_CODE (arg) != SCOPE_REF, 313);
if (TREE_CODE (arg) != OFFSET_REF)
return 0;
t = TREE_OPERAND (arg, 1);
/* Check all this code for right semantics. */
if (TREE_CODE (t) == FUNCTION_DECL)
{
if (DECL_DESTRUCTOR_P (t))
error ("taking address of destructor");
return build_unary_op (ADDR_EXPR, t, 0);
}
if (TREE_CODE (t) == VAR_DECL)
return build_unary_op (ADDR_EXPR, t, 0);
else
{
tree type;
if (TREE_OPERAND (arg, 0)
&& ! is_dummy_object (TREE_OPERAND (arg, 0))
&& TREE_CODE (t) != FIELD_DECL)
{
error ("taking address of bound pointer-to-member expression");
return error_mark_node;
}
type = build_offset_type (DECL_FIELD_CONTEXT (t), TREE_TYPE (t));
type = build_pointer_type (type);
t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
return t;
}
}
/* We permit compiler to make function calls returning
objects of aggregate type look like lvalues. */
{
tree targ = arg;
if (TREE_CODE (targ) == SAVE_EXPR)
targ = TREE_OPERAND (targ, 0);
if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (TREE_TYPE (targ)))
{
if (TREE_CODE (arg) == SAVE_EXPR)
targ = arg;
else
targ = build_cplus_new (TREE_TYPE (arg), arg);
return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
}
if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
return build (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
TREE_OPERAND (targ, 0), current_function_decl, NULL);
}
/* Don't let anything else be handled specially. */
return 0;
}
/* Mark EXP saying that we need to be able to take the
address of it; it should not be allocated in a register.
Value is 1 if successful.
C++: we do not allow `current_class_ptr' to be addressable. */
int
mark_addressable (exp)
tree exp;
{
register tree x = exp;
if (TREE_ADDRESSABLE (x) == 1)
return 1;
while (1)
switch (TREE_CODE (x))
{
case ADDR_EXPR:
case COMPONENT_REF:
case ARRAY_REF:
case REALPART_EXPR:
case IMAGPART_EXPR:
x = TREE_OPERAND (x, 0);
break;
case PARM_DECL:
if (x == current_class_ptr)
{
error ("cannot take the address of `this', which is an rvalue expression");
TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later */
return 1;
}
case VAR_DECL:
/* Caller should not be trying to mark initialized
constant fields addressable. */
my_friendly_assert (DECL_LANG_SPECIFIC (x) == 0
|| DECL_IN_AGGR_P (x) == 0
|| TREE_STATIC (x)
|| DECL_EXTERNAL (x), 314);
case CONST_DECL:
case RESULT_DECL:
if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
&& !DECL_ARTIFICIAL (x) && extra_warnings)
warning ("address requested for `%D', which is declared `register'",
x);
TREE_ADDRESSABLE (x) = 1;
return 1;
case FUNCTION_DECL:
TREE_ADDRESSABLE (x) = 1;
TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
return 1;
case CONSTRUCTOR:
TREE_ADDRESSABLE (x) = 1;
return 1;
case TARGET_EXPR:
TREE_ADDRESSABLE (x) = 1;
mark_addressable (TREE_OPERAND (x, 0));
return 1;
default:
return 1;
}
}
/* Build and return a conditional expression IFEXP ? OP1 : OP2. */
tree
build_x_conditional_expr (ifexp, op1, op2)
tree ifexp, op1, op2;
{
if (processing_template_decl)
return build_min_nt (COND_EXPR, ifexp, op1, op2);
return build_conditional_expr (ifexp, op1, op2);
}
/* Handle overloading of the ',' operator when needed. Otherwise,
this function just builds an expression list. */
tree
build_x_compound_expr (list)
tree list;
{
tree rest = TREE_CHAIN (list);
tree result;
if (processing_template_decl)
return build_min_nt (COMPOUND_EXPR, list, NULL_TREE);
if (rest == NULL_TREE)
return build_compound_expr (list);
result = build_opfncall (COMPOUND_EXPR, LOOKUP_NORMAL,
TREE_VALUE (list), TREE_VALUE (rest), NULL_TREE);
if (result)
return build_x_compound_expr (tree_cons (NULL_TREE, result,
TREE_CHAIN (rest)));
if (! TREE_SIDE_EFFECTS (TREE_VALUE (list)))
{
/* FIXME: This test should be in the implicit cast to void of the LHS. */
/* the left-hand operand of a comma expression is like an expression
statement: we should warn if it doesn't have any side-effects,
unless it was explicitly cast to (void). */
if ((extra_warnings || warn_unused_value)
&& !(TREE_CODE (TREE_VALUE(list)) == CONVERT_EXPR
&& VOID_TYPE_P (TREE_TYPE (TREE_VALUE(list)))))
warning("left-hand operand of comma expression has no effect");
}
#if 0 /* this requires a gcc backend patch to export warn_if_unused_value */
else if (warn_unused_value)
warn_if_unused_value (TREE_VALUE(list));
#endif
return build_compound_expr
(tree_cons (NULL_TREE, TREE_VALUE (list),
build_tree_list (NULL_TREE,
build_x_compound_expr (rest))));
}
/* Given a list of expressions, return a compound expression
that performs them all and returns the value of the last of them. */
tree
build_compound_expr (list)
tree list;
{
register tree rest;
tree first;
TREE_VALUE (list) = decl_constant_value (TREE_VALUE (list));
if (TREE_CHAIN (list) == 0)
{
/* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
Strip such NOP_EXPRs, since LIST is used in non-lvalue context. */
if (TREE_CODE (list) == NOP_EXPR
&& TREE_TYPE (list) == TREE_TYPE (TREE_OPERAND (list, 0)))
list = TREE_OPERAND (list, 0);
return TREE_VALUE (list);
}
first = TREE_VALUE (list);
first = convert_to_void (first, "left-hand operand of comma");
if (first == error_mark_node)
return error_mark_node;
rest = build_compound_expr (TREE_CHAIN (list));
if (rest == error_mark_node)
return error_mark_node;
/* When pedantic, a compound expression cannot be a constant expression. */
if (! TREE_SIDE_EFFECTS (first) && ! pedantic)
return rest;
return build (COMPOUND_EXPR, TREE_TYPE (rest), first, rest);
}
tree
build_static_cast (type, expr)
tree type, expr;
{
tree intype;
int ok;
if (type == error_mark_node || expr == error_mark_node)
return error_mark_node;
if (TREE_CODE (expr) == OFFSET_REF)
expr = resolve_offset_ref (expr);
if (processing_template_decl)
{
tree t = build_min (STATIC_CAST_EXPR, type, expr);
return t;
}
/* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
if (TREE_CODE (type) != REFERENCE_TYPE
&& TREE_CODE (expr) == NOP_EXPR
&& TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
expr = TREE_OPERAND (expr, 0);
if (TREE_CODE (type) == VOID_TYPE)
{
expr = convert_to_void (expr, /*implicit=*/NULL);
return expr;
}
if (TREE_CODE (type) == REFERENCE_TYPE)
return (convert_from_reference
(convert_to_reference (type, expr, CONV_STATIC|CONV_IMPLICIT,
LOOKUP_COMPLAIN, NULL_TREE)));
if (IS_AGGR_TYPE (type))
return build_cplus_new (type, (build_method_call
(NULL_TREE, complete_ctor_identifier,
build_tree_list (NULL_TREE, expr),
TYPE_BINFO (type), LOOKUP_NORMAL)));
intype = TREE_TYPE (expr);
/* FIXME handle casting to array type. */
ok = 0;
if (IS_AGGR_TYPE (intype)
? can_convert_arg (type, intype, expr)
: can_convert_arg (strip_all_pointer_quals (type),
strip_all_pointer_quals (intype), expr))
/* This is a standard conversion. */
ok = 1;
else if (TYPE_PTROB_P (type) && TYPE_PTROB_P (intype))
{
/* They're pointers to objects. They must be aggregates that
are related non-virtually. */
base_kind kind;
if (IS_AGGR_TYPE (TREE_TYPE (type)) && IS_AGGR_TYPE (TREE_TYPE (intype))
&& lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
ba_ignore | ba_quiet, &kind)
&& kind != bk_via_virtual)
ok = 1;
}
else if (TREE_CODE (intype) != BOOLEAN_TYPE
&& TREE_CODE (type) != ARRAY_TYPE
&& TREE_CODE (type) != FUNCTION_TYPE
&& can_convert (intype, strip_all_pointer_quals (type)))
ok = 1;
else if (TREE_CODE (intype) == ENUMERAL_TYPE
&& TREE_CODE (type) == ENUMERAL_TYPE)
/* DR 128: "A value of integral _or enumeration_ type can be explicitly
converted to an enumeration type."
The integral to enumeration will be accepted by the previous clause.
We need to explicitly check for enumeration to enumeration. */
ok = 1;
/* [expr.static.cast]
The static_cast operator shall not be used to cast away
constness. */
if (ok && casts_away_constness (intype, type))
{
error ("static_cast from type `%T' to type `%T' casts away constness",
intype, type);
return error_mark_node;
}
if (ok)
return build_c_cast (type, expr);
error ("invalid static_cast from type `%T' to type `%T'", intype, type);
return error_mark_node;
}
tree
build_reinterpret_cast (type, expr)
tree type, expr;
{
tree intype;
if (type == error_mark_node || expr == error_mark_node)
return error_mark_node;
if (TREE_CODE (expr) == OFFSET_REF)
expr = resolve_offset_ref (expr);
if (processing_template_decl)
{
tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
return t;
}
if (TREE_CODE (type) != REFERENCE_TYPE)
{
expr = decay_conversion (expr);
/* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
if (TREE_CODE (expr) == NOP_EXPR
&& TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
expr = TREE_OPERAND (expr, 0);
}
intype = TREE_TYPE (expr);
if (TREE_CODE (type) == REFERENCE_TYPE)
{
if (! real_lvalue_p (expr))
{
error ("invalid reinterpret_cast of an rvalue expression of type `%T' to type `%T'", intype, type);
return error_mark_node;
}
expr = build_unary_op (ADDR_EXPR, expr, 0);
if (expr != error_mark_node)
expr = build_reinterpret_cast
(build_pointer_type (TREE_TYPE (type)), expr);
if (expr != error_mark_node)
expr = build_indirect_ref (expr, 0);
return expr;
}
else if (same_type_ignoring_top_level_qualifiers_p (intype, type))
return build_static_cast (type, expr);
if (TYPE_PTR_P (type) && (TREE_CODE (intype) == INTEGER_TYPE
|| TREE_CODE (intype) == ENUMERAL_TYPE))
/* OK */;
else if (TREE_CODE (type) == INTEGER_TYPE && TYPE_PTR_P (intype))
{
if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
pedwarn ("reinterpret_cast from `%T' to `%T' loses precision",
intype, type);
}
else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
|| (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
{
expr = decl_constant_value (expr);
return fold (build1 (NOP_EXPR, type, expr));
}
else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
|| (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
{
if (! comp_ptr_ttypes_reinterpret (TREE_TYPE (type), TREE_TYPE (intype)))
pedwarn ("reinterpret_cast from `%T' to `%T' casts away const (or volatile)",
intype, type);
expr = decl_constant_value (expr);
return fold (build1 (NOP_EXPR, type, expr));
}
else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
|| (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
{
pedwarn ("ISO C++ forbids casting between pointer-to-function and pointer-to-object");
expr = decl_constant_value (expr);
return fold (build1 (NOP_EXPR, type, expr));
}
else
{
error ("invalid reinterpret_cast from type `%T' to type `%T'",
intype, type);
return error_mark_node;
}
return cp_convert (type, expr);
}
tree
build_const_cast (type, expr)
tree type, expr;
{
tree intype;
if (type == error_mark_node || expr == error_mark_node)
return error_mark_node;
if (TREE_CODE (expr) == OFFSET_REF)
expr = resolve_offset_ref (expr);
if (processing_template_decl)
{
tree t = build_min (CONST_CAST_EXPR, type, expr);
return t;
}
if (!POINTER_TYPE_P (type))
error ("invalid use of const_cast with type `%T', which is not a pointer, reference, nor a pointer-to-data-member type", type);
else if (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
{
error ("invalid use of const_cast with type `%T', which is a pointer or reference to a function type", type);
return error_mark_node;
}
if (TREE_CODE (type) != REFERENCE_TYPE)
{
expr = decay_conversion (expr);
/* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
if (TREE_CODE (expr) == NOP_EXPR
&& TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
expr = TREE_OPERAND (expr, 0);
}
intype = TREE_TYPE (expr);
if (same_type_ignoring_top_level_qualifiers_p (intype, type))
return build_static_cast (type, expr);
else if (TREE_CODE (type) == REFERENCE_TYPE)
{
if (! real_lvalue_p (expr))
{
error ("invalid const_cast of an rvalue of type `%T' to type `%T'", intype, type);
return error_mark_node;
}
if (comp_ptr_ttypes_const (TREE_TYPE (type), intype))
{
expr = build_unary_op (ADDR_EXPR, expr, 0);
expr = build1 (NOP_EXPR, type, expr);
return convert_from_reference (expr);
}
}
else if (TREE_CODE (type) == POINTER_TYPE
&& TREE_CODE (intype) == POINTER_TYPE
&& comp_ptr_ttypes_const (TREE_TYPE (type), TREE_TYPE (intype)))
return cp_convert (type, expr);
error ("invalid const_cast from type `%T' to type `%T'", intype, type);
return error_mark_node;
}
/* Build an expression representing a cast to type TYPE of expression EXPR.
ALLOW_NONCONVERTING is true if we should allow non-converting constructors
when doing the cast. */
tree
build_c_cast (type, expr)
tree type, expr;
{
register tree value = expr;
tree otype;
if (type == error_mark_node || expr == error_mark_node)
return error_mark_node;
if (processing_template_decl)
{
tree t = build_min (CAST_EXPR, type,
tree_cons (NULL_TREE, value, NULL_TREE));
return t;
}
/* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
if (TREE_CODE (type) != REFERENCE_TYPE
&& TREE_CODE (value) == NOP_EXPR
&& TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
value = TREE_OPERAND (value, 0);
if (TREE_CODE (value) == OFFSET_REF)
value = resolve_offset_ref (value);
if (TREE_CODE (type) == ARRAY_TYPE)
{
/* Allow casting from T1* to T2[] because Cfront allows it.
NIHCL uses it. It is not valid ISO C++ however. */
if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
{
pedwarn ("ISO C++ forbids casting to an array type `%T'", type);
type = build_pointer_type (TREE_TYPE (type));
}
else
{
error ("ISO C++ forbids casting to an array type `%T'", type);
return error_mark_node;
}
}
if (TREE_CODE (type) == FUNCTION_TYPE
|| TREE_CODE (type) == METHOD_TYPE)
{
error ("invalid cast to function type `%T'", type);
return error_mark_node;
}
if (TREE_CODE (type) == VOID_TYPE)
{
/* Conversion to void does not cause any of the normal function to
* pointer, array to pointer and lvalue to rvalue decays. */
value = convert_to_void (value, /*implicit=*/NULL);
return value;
}
/* Convert functions and arrays to pointers and
convert references to their expanded types,
but don't convert any other types. If, however, we are
casting to a class type, there's no reason to do this: the
cast will only succeed if there is a converting constructor,
and the default conversions will be done at that point. In
fact, doing the default conversion here is actually harmful
in cases like this:
typedef int A[2];
struct S { S(const A&); };
since we don't want the array-to-pointer conversion done. */
if (!IS_AGGR_TYPE (type))
{
if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
|| (TREE_CODE (TREE_TYPE (value)) == METHOD_TYPE
/* Don't do the default conversion on a ->* expression. */
&& ! (TREE_CODE (type) == POINTER_TYPE
&& bound_pmf_p (value)))
|| TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
|| TREE_CODE (TREE_TYPE (value)) == REFERENCE_TYPE)
value = default_conversion (value);
}
else if (TREE_CODE (TREE_TYPE (value)) == REFERENCE_TYPE)
/* However, even for class types, we still need to strip away
the reference type, since the call to convert_force below
does not expect the input expression to be of reference
type. */
value = convert_from_reference (value);
otype = TREE_TYPE (value);
/* Optionally warn about potentially worrisome casts. */
if (warn_cast_qual
&& TREE_CODE (type) == POINTER_TYPE
&& TREE_CODE (otype) == POINTER_TYPE
&& !at_least_as_qualified_p (TREE_TYPE (type),
TREE_TYPE (otype)))
warning ("cast from `%T' to `%T' discards qualifiers from pointer target type",
otype, type);
if (TREE_CODE (type) == INTEGER_TYPE
&& TREE_CODE (otype) == POINTER_TYPE
&& TYPE_PRECISION (type) != TYPE_PRECISION (otype))
warning ("cast from pointer to integer of different size");
if (TREE_CODE (type) == POINTER_TYPE
&& TREE_CODE (otype) == INTEGER_TYPE
&& TYPE_PRECISION (type) != TYPE_PRECISION (otype)
/* Don't warn about converting any constant. */
&& !TREE_CONSTANT (value))
warning ("cast to pointer from integer of different size");
if (TREE_CODE (type) == REFERENCE_TYPE)
value = (convert_from_reference
(convert_to_reference (type, value, CONV_C_CAST,
LOOKUP_COMPLAIN, NULL_TREE)));
else
{
tree ovalue;
value = decl_constant_value (value);
ovalue = value;
value = convert_force (type, value, CONV_C_CAST);
/* Ignore any integer overflow caused by the cast. */
if (TREE_CODE (value) == INTEGER_CST)
{
TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
}
}
/* Warn about possible alignment problems. Do this here when we will have
instantiated any necessary template types. */
if (STRICT_ALIGNMENT && warn_cast_align
&& TREE_CODE (type) == POINTER_TYPE
&& TREE_CODE (otype) == POINTER_TYPE
&& TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
&& TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
&& COMPLETE_TYPE_P (TREE_TYPE (otype))
&& COMPLETE_TYPE_P (TREE_TYPE (type))
&& TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
warning ("cast from `%T' to `%T' increases required alignment of target type",
otype, type);
/* Always produce some operator for an explicit cast,
so we can tell (for -pedantic) that the cast is no lvalue. */
if (TREE_CODE (type) != REFERENCE_TYPE && value == expr
&& real_lvalue_p (value))
value = non_lvalue (value);
return value;
}
/* Build an assignment expression of lvalue LHS from value RHS.
MODIFYCODE is the code for a binary operator that we use
to combine the old value of LHS with RHS to get the new value.
Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
tree
build_modify_expr (lhs, modifycode, rhs)
tree lhs;
enum tree_code modifycode;
tree rhs;
{
register tree result;
tree newrhs = rhs;
tree lhstype = TREE_TYPE (lhs);
tree olhstype = lhstype;
tree olhs = lhs;
/* Avoid duplicate error messages from operands that had errors. */
if (lhs == error_mark_node || rhs == error_mark_node)
return error_mark_node;
/* Types that aren't fully specified cannot be used in assignments. */
lhs = require_complete_type (lhs);
newrhs = rhs;
/* Handle control structure constructs used as "lvalues". */
switch (TREE_CODE (lhs))
{
/* Handle --foo = 5; as these are valid constructs in C++ */
case PREDECREMENT_EXPR:
case PREINCREMENT_EXPR:
if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
lhs = build (TREE_CODE (lhs), TREE_TYPE (lhs),
stabilize_reference (TREE_OPERAND (lhs, 0)),
TREE_OPERAND (lhs, 1));
return build (COMPOUND_EXPR, lhstype,
lhs,
build_modify_expr (TREE_OPERAND (lhs, 0),
modifycode, rhs));
/* Handle (a, b) used as an "lvalue". */
case COMPOUND_EXPR:
newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
modifycode, rhs);
if (newrhs == error_mark_node)
return error_mark_node;
return build (COMPOUND_EXPR, lhstype,
TREE_OPERAND (lhs, 0), newrhs);
case MODIFY_EXPR:
newrhs = build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs);
if (newrhs == error_mark_node)
return error_mark_node;
return build (COMPOUND_EXPR, lhstype, lhs, newrhs);
/* Handle (a ? b : c) used as an "lvalue". */
case COND_EXPR:
rhs = save_expr (rhs);
{
/* Produce (a ? (b = rhs) : (c = rhs))
except that the RHS goes through a save-expr
so the code to compute it is only emitted once. */
tree cond;
/* Check this here to avoid odd errors when trying to convert
a throw to the type of the COND_EXPR. */
if (!lvalue_or_else (lhs, "assignment"))
return error_mark_node;
cond = build_conditional_expr
(TREE_OPERAND (lhs, 0),
build_modify_expr (cp_convert (TREE_TYPE (lhs),
TREE_OPERAND (lhs, 1)),
modifycode, rhs),
build_modify_expr (cp_convert (TREE_TYPE (lhs),
TREE_OPERAND (lhs, 2)),
modifycode, rhs));
if (cond == error_mark_node)
return cond;
/* Make sure the code to compute the rhs comes out
before the split. */
return build (COMPOUND_EXPR, TREE_TYPE (lhs),
/* Case to void to suppress warning
from warn_if_unused_value. */
cp_convert (void_type_node, rhs), cond);
}
default:
break;
}
if (TREE_CODE (lhs) == OFFSET_REF)
{
if (TREE_OPERAND (lhs, 0) == NULL_TREE)
{
/* Static class member? */
tree member = TREE_OPERAND (lhs, 1);
if (TREE_CODE (member) == VAR_DECL)
lhs = member;
else
{
compiler_error ("invalid static class member");
return error_mark_node;
}
}
else
lhs = resolve_offset_ref (lhs);
olhstype = lhstype = TREE_TYPE (lhs);
}
if (lhs == error_mark_node)
return lhs;
if (TREE_CODE (lhstype) == REFERENCE_TYPE
&& modifycode != INIT_EXPR)
{
lhs = convert_from_reference (lhs);
olhstype = lhstype = TREE_TYPE (lhs);
}
/* If a binary op has been requested, combine the old LHS value with the RHS
producing the value we should actually store into the LHS. */
if (modifycode == INIT_EXPR)
{
if (TREE_CODE (rhs) == CONSTRUCTOR)
{
if (! same_type_p (TREE_TYPE (rhs), lhstype))
abort ();
result = build (INIT_EXPR, lhstype, lhs, rhs);
TREE_SIDE_EFFECTS (result) = 1;
return result;
}
else if (! IS_AGGR_TYPE (lhstype))
/* Do the default thing */;
else
{
result = build_method_call (lhs, complete_ctor_identifier,
build_tree_list (NULL_TREE, rhs),
TYPE_BINFO (lhstype), LOOKUP_NORMAL);
if (result == NULL_TREE)
return error_mark_node;
return result;
}
}
else if (modifycode == NOP_EXPR)
{
/* `operator=' is not an inheritable operator. */
if (! IS_AGGR_TYPE (lhstype))
/* Do the default thing */;
else
{
result = build_opfncall (MODIFY_EXPR, LOOKUP_NORMAL,
lhs, rhs, make_node (NOP_EXPR));
if (result == NULL_TREE)
return error_mark_node;
return result;
}
lhstype = olhstype;
}
else if (PROMOTES_TO_AGGR_TYPE (lhstype, REFERENCE_TYPE))
{
my_friendly_abort (978652);
}
else
{
lhs = stabilize_reference (lhs);
newrhs = cp_build_binary_op (modifycode, lhs, rhs);
if (newrhs == error_mark_node)
{
error (" in evaluation of `%Q(%#T, %#T)'", modifycode,
TREE_TYPE (lhs), TREE_TYPE (rhs));
return error_mark_node;
}
}
/* Handle a cast used as an "lvalue".
We have already performed any binary operator using the value as cast.
Now convert the result to the cast type of the lhs,
and then true type of the lhs and store it there;
then convert result back to the cast type to be the value
of the assignment. */
switch (TREE_CODE (lhs))
{
case NOP_EXPR:
case CONVERT_EXPR:
case FLOAT_EXPR:
case FIX_TRUNC_EXPR:
case FIX_FLOOR_EXPR:
case FIX_ROUND_EXPR:
case FIX_CEIL_EXPR:
if (TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
|| TREE_CODE (TREE_TYPE (newrhs)) == FUNCTION_TYPE
|| TREE_CODE (TREE_TYPE (newrhs)) == METHOD_TYPE
|| TREE_CODE (TREE_TYPE (newrhs)) == OFFSET_TYPE)
newrhs = default_conversion (newrhs);
{
tree inner_lhs = TREE_OPERAND (lhs, 0);
tree result;
/* ISO C++ 5.4/1: The result is an lvalue if T is a reference
type, otherwise the result is an rvalue. */
if (! lvalue_p (lhs))
pedwarn ("ISO C++ forbids cast to non-reference type used as lvalue");
result = build_modify_expr (inner_lhs, NOP_EXPR,
cp_convert (TREE_TYPE (inner_lhs),
cp_convert (lhstype, newrhs)));
if (result == error_mark_node)
return result;
return cp_convert (TREE_TYPE (lhs), result);
}
default:
break;
}
/* Now we have handled acceptable kinds of LHS that are not truly lvalues.
Reject anything strange now. */
if (!lvalue_or_else (lhs, "assignment"))
return error_mark_node;
GNU_xref_assign (lhs);
/* Warn about storing in something that is `const'. */
/* For C++, don't warn if this is initialization. */
if (modifycode != INIT_EXPR
&& (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
/* Functions are not modifiable, even though they are
lvalues. */
|| TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
|| (IS_AGGR_TYPE_CODE (TREE_CODE (lhstype))
&& C_TYPE_FIELDS_READONLY (lhstype))
|| (TREE_CODE (lhstype) == REFERENCE_TYPE
&& CP_TYPE_CONST_P (TREE_TYPE (lhstype)))))
readonly_error (lhs, "assignment", 0);
/* If storing into a structure or union member,
it has probably been given type `int'.
Compute the type that would go with
the actual amount of storage the member occupies. */
if (TREE_CODE (lhs) == COMPONENT_REF
&& (TREE_CODE (lhstype) == INTEGER_TYPE
|| TREE_CODE (lhstype) == REAL_TYPE
|| TREE_CODE (lhstype) == ENUMERAL_TYPE))
{
lhstype = TREE_TYPE (get_unwidened (lhs, 0));
/* If storing in a field that is in actuality a short or narrower
than one, we must store in the field in its actual type. */
if (lhstype != TREE_TYPE (lhs))
{
lhs = copy_node (lhs);
TREE_TYPE (lhs) = lhstype;
}
}
if (modifycode != INIT_EXPR)
{
/* Make modifycode now either a NOP_EXPR or an INIT_EXPR. */
modifycode = NOP_EXPR;
/* Reference-bashing */
if (TREE_CODE (lhstype) == REFERENCE_TYPE)
{
tree tmp = convert_from_reference (lhs);
lhstype = TREE_TYPE (tmp);
if (!COMPLETE_TYPE_P (lhstype))
{
incomplete_type_error (lhs, lhstype);
return error_mark_node;
}
lhs = tmp;
olhstype = lhstype;
}
if (TREE_CODE (TREE_TYPE (newrhs)) == REFERENCE_TYPE)
{
tree tmp = convert_from_reference (newrhs);
if (!COMPLETE_TYPE_P (TREE_TYPE (tmp)))
{
incomplete_type_error (newrhs, TREE_TYPE (tmp));
return error_mark_node;
}
newrhs = tmp;
}
}
if (TREE_SIDE_EFFECTS (lhs))
lhs = stabilize_reference (lhs);
if (TREE_SIDE_EFFECTS (newrhs))
newrhs = stabilize_reference (newrhs);
/* Convert new value to destination type. */
if (TREE_CODE (lhstype) == ARRAY_TYPE)
{
int from_array;
if (!same_or_base_type_p (lhstype, TREE_TYPE (rhs)))
{
error ("incompatible types in assignment of `%T' to `%T'",
TREE_TYPE (rhs), lhstype);
return error_mark_node;
}
/* Allow array assignment in compiler-generated code. */
if (pedantic && ! DECL_ARTIFICIAL (current_function_decl))
pedwarn ("ISO C++ forbids assignment of arrays");
from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
? 1 + (modifycode != INIT_EXPR): 0;
return build_vec_init (lhs, newrhs, from_array);
}
if (modifycode == INIT_EXPR)
{
newrhs = convert_for_initialization (lhs, lhstype, newrhs, LOOKUP_NORMAL,
"initialization", NULL_TREE, 0);
if (current_function_decl &&
lhs == DECL_RESULT (current_function_decl))
{
if (DECL_INITIAL (lhs))
warning ("return value from function receives multiple initializations");
DECL_INITIAL (lhs) = newrhs;
}
}
else
{
/* Avoid warnings on enum bit fields. */
if (TREE_CODE (olhstype) == ENUMERAL_TYPE
&& TREE_CODE (lhstype) == INTEGER_TYPE)
{
newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
NULL_TREE, 0);
newrhs = convert_force (lhstype, newrhs, 0);
}
else
newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
NULL_TREE, 0);
if (TREE_CODE (newrhs) == CALL_EXPR
&& TYPE_NEEDS_CONSTRUCTING (lhstype))
newrhs = build_cplus_new (lhstype, newrhs);
/* Can't initialize directly from a TARGET_EXPR, since that would
cause the lhs to be constructed twice, and possibly result in
accidental self-initialization. So we force the TARGET_EXPR to be
expanded without a target. */
if (TREE_CODE (newrhs) == TARGET_EXPR)
newrhs = build (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
TREE_OPERAND (newrhs, 0));
}
if (newrhs == error_mark_node)
return error_mark_node;
if (TREE_CODE (newrhs) == COND_EXPR)
{
tree lhs1;
tree cond = TREE_OPERAND (newrhs, 0);
if (TREE_SIDE_EFFECTS (lhs))
cond = build_compound_expr (tree_cons
(NULL_TREE, lhs,
build_tree_list (NULL_TREE, cond)));
/* Cannot have two identical lhs on this one tree (result) as preexpand
calls will rip them out and fill in RTL for them, but when the
rtl is generated, the calls will only be in the first side of the
condition, not on both, or before the conditional jump! (mrs) */
lhs1 = break_out_calls (lhs);
if (lhs == lhs1)
/* If there's no change, the COND_EXPR behaves like any other rhs. */
result = build (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
lhstype, lhs, newrhs);
else
{
tree result_type = TREE_TYPE (newrhs);
/* We have to convert each arm to the proper type because the
types may have been munged by constant folding. */
result
= build (COND_EXPR, result_type, cond,
build_modify_expr (lhs, modifycode,
cp_convert (result_type,
TREE_OPERAND (newrhs, 1))),
build_modify_expr (lhs1, modifycode,
cp_convert (result_type,
TREE_OPERAND (newrhs, 2))));
}
}
else
result = build (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
lhstype, lhs, newrhs);
TREE_SIDE_EFFECTS (result) = 1;
/* If we got the LHS in a different type for storing in,
convert the result back to the nominal type of LHS
so that the value we return always has the same type
as the LHS argument. */
if (olhstype == TREE_TYPE (result))
return result;
/* Avoid warnings converting integral types back into enums
for enum bit fields. */
if (TREE_CODE (TREE_TYPE (result)) == INTEGER_TYPE
&& TREE_CODE (olhstype) == ENUMERAL_TYPE)
{
result = build (COMPOUND_EXPR, olhstype, result, olhs);
TREE_NO_UNUSED_WARNING (result) = 1;
return result;
}
return convert_for_assignment (olhstype, result, "assignment",
NULL_TREE, 0);
}
tree
build_x_modify_expr (lhs, modifycode, rhs)
tree lhs;
enum tree_code modifycode;
tree rhs;
{
if (processing_template_decl)
return build_min_nt (MODOP_EXPR, lhs,
build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
if (modifycode != NOP_EXPR)
{
tree rval = build_opfncall (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
make_node (modifycode));
if (rval)
return rval;
}
return build_modify_expr (lhs, modifycode, rhs);
}
/* Get difference in deltas for different pointer to member function
types. Return integer_zero_node, if FROM cannot be converted to a
TO type. If FORCE is true, then allow reverse conversions as well.
Note that the naming of FROM and TO is kind of backwards; the return
value is what we add to a TO in order to get a FROM. They are named
this way because we call this function to find out how to convert from
a pointer to member of FROM to a pointer to member of TO. */
static tree
get_delta_difference (from, to, force)
tree from, to;
int force;
{
tree delta = integer_zero_node;
tree binfo;
tree virt_binfo;
base_kind kind;
binfo = lookup_base (to, from, ba_check, &kind);
if (kind == bk_inaccessible || kind == bk_ambig)
{
error (" in pointer to member function conversion");
return delta;
}
if (!binfo)
{
if (!force)
{
error_not_base_type (from, to);
error (" in pointer to member conversion");
return delta;
}
binfo = lookup_base (from, to, ba_check, &kind);
if (binfo == 0)
return delta;
virt_binfo = binfo_from_vbase (binfo);
if (virt_binfo)
{
/* This is a reinterpret cast, we choose to do nothing. */
warning ("pointer to member cast via virtual base `%T' of `%T'",
BINFO_TYPE (virt_binfo),
BINFO_TYPE (BINFO_INHERITANCE_CHAIN (virt_binfo)));
return delta;
}
delta = BINFO_OFFSET (binfo);
delta = cp_convert (ptrdiff_type_node, delta);
delta = cp_build_binary_op (MINUS_EXPR,
integer_zero_node,
delta);
return delta;
}
virt_binfo = binfo_from_vbase (binfo);
if (virt_binfo)
{
/* This is a reinterpret cast, we choose to do nothing. */
if (force)
warning ("pointer to member cast via virtual base `%T' of `%T'",
BINFO_TYPE (virt_binfo),
BINFO_TYPE (BINFO_INHERITANCE_CHAIN (virt_binfo)));
else
error ("pointer to member conversion via virtual base `%T' of `%T'",
BINFO_TYPE (virt_binfo),
BINFO_TYPE (BINFO_INHERITANCE_CHAIN (virt_binfo)));
return delta;
}
delta = BINFO_OFFSET (binfo);
return cp_convert (ptrdiff_type_node, delta);
}
/* Return a constructor for the pointer-to-member-function TYPE using
the other components as specified. */
tree
build_ptrmemfunc1 (type, delta, pfn)
tree type, delta, pfn;
{
tree u = NULL_TREE;
tree delta_field;
tree pfn_field;
/* Pull the FIELD_DECLs out of the type. */
pfn_field = TYPE_FIELDS (type);
delta_field = TREE_CHAIN (pfn_field);
/* Make sure DELTA has the type we want. */
delta = convert_and_check (delta_type_node, delta);
/* Finish creating the initializer. */
u = tree_cons (pfn_field, pfn,
build_tree_list (delta_field, delta));
u = build (CONSTRUCTOR, type, NULL_TREE, u);
TREE_CONSTANT (u) = TREE_CONSTANT (pfn) && TREE_CONSTANT (delta);
TREE_STATIC (u) = (TREE_CONSTANT (u)
&& (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
!= NULL_TREE)
&& (initializer_constant_valid_p (delta, TREE_TYPE (delta))
!= NULL_TREE));
return u;
}
/* Build a constructor for a pointer to member function. It can be
used to initialize global variables, local variable, or used
as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
want to be.
If FORCE is non-zero, then force this conversion, even if
we would rather not do it. Usually set when using an explicit
cast.
Return error_mark_node, if something goes wrong. */
tree
build_ptrmemfunc (type, pfn, force)
tree type, pfn;
int force;
{
tree fn;
tree pfn_type = TREE_TYPE (pfn);
tree to_type = build_ptrmemfunc_type (type);
/* Handle multiple conversions of pointer to member functions. */
if (TYPE_PTRMEMFUNC_P (TREE_TYPE (pfn)))
{
tree delta = NULL_TREE;
tree npfn = NULL_TREE;
tree n;
if (!force
&& !can_convert_arg (to_type, TREE_TYPE (pfn), pfn))
error ("invalid conversion to type `%T' from type `%T'",
to_type, pfn_type);
n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
force);
/* We don't have to do any conversion to convert a
pointer-to-member to its own type. But, we don't want to
just return a PTRMEM_CST if there's an explicit cast; that
cast should make the expression an invalid template argument. */
if (TREE_CODE (pfn) != PTRMEM_CST)
{
if (same_type_p (to_type, pfn_type))
return pfn;
else if (integer_zerop (n))
return build_reinterpret_cast (to_type, pfn);
}
if (TREE_SIDE_EFFECTS (pfn))
pfn = save_expr (pfn);
/* Obtain the function pointer and the current DELTA. */
if (TREE_CODE (pfn) == PTRMEM_CST)
expand_ptrmemfunc_cst (pfn, &delta, &npfn);
else
{
npfn = build_component_ref (pfn, pfn_identifier, NULL_TREE, 0);
delta = build_component_ref (pfn, delta_identifier, NULL_TREE, 0);
}
/* Just adjust the DELTA field. */
delta = cp_convert (ptrdiff_type_node, delta);
if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
n = cp_build_binary_op (LSHIFT_EXPR, n, integer_one_node);
delta = cp_build_binary_op (PLUS_EXPR, delta, n);
return build_ptrmemfunc1 (to_type, delta, npfn);
}
/* Handle null pointer to member function conversions. */
if (integer_zerop (pfn))
{
pfn = build_c_cast (type, integer_zero_node);
return build_ptrmemfunc1 (to_type,
integer_zero_node,
pfn);
}
if (type_unknown_p (pfn))
return instantiate_type (type, pfn, itf_complain);
fn = TREE_OPERAND (pfn, 0);
my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 0);
return make_ptrmem_cst (to_type, fn);
}
/* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
given by CST.
??? There is no consistency as to the types returned for the above
values. Some code acts as if its a sizetype and some as if its
integer_type_node. */
void
expand_ptrmemfunc_cst (cst, delta, pfn)
tree cst;
tree *delta;
tree *pfn;
{
tree type = TREE_TYPE (cst);
tree fn = PTRMEM_CST_MEMBER (cst);
tree ptr_class, fn_class;
my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 0);
/* The class that the function belongs to. */
fn_class = DECL_CONTEXT (fn);
/* The class that we're creating a pointer to member of. */
ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
/* First, calculate the adjustment to the function's class. */
*delta = get_delta_difference (fn_class, ptr_class, /*force=*/0);
if (!DECL_VIRTUAL_P (fn))
*pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
else
{
/* If we're dealing with a virtual function, we have to adjust 'this'
again, to point to the base which provides the vtable entry for
fn; the call will do the opposite adjustment. */
tree orig_class = DECL_VIRTUAL_CONTEXT (fn);
tree binfo = binfo_or_else (orig_class, fn_class);
*delta = fold (build (PLUS_EXPR, TREE_TYPE (*delta),
*delta, BINFO_OFFSET (binfo)));
/* We set PFN to the vtable offset at which the function can be
found, plus one (unless ptrmemfunc_vbit_in_delta, in which
case delta is shifted left, and then incremented). */
*pfn = DECL_VINDEX (fn);
*pfn = fold (build (MULT_EXPR, integer_type_node, *pfn,
TYPE_SIZE_UNIT (vtable_entry_type)));
switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
{
case ptrmemfunc_vbit_in_pfn:
*pfn = fold (build (PLUS_EXPR, integer_type_node, *pfn,
integer_one_node));
break;
case ptrmemfunc_vbit_in_delta:
*delta = fold (build (LSHIFT_EXPR, TREE_TYPE (*delta),
*delta, integer_one_node));
*delta = fold (build (PLUS_EXPR, TREE_TYPE (*delta),
*delta, integer_one_node));
break;
default:
abort ();
}
*pfn = fold (build1 (NOP_EXPR, TYPE_PTRMEMFUNC_FN_TYPE (type),
*pfn));
}
}
/* Return an expression for PFN from the pointer-to-member function
given by T. */
tree
pfn_from_ptrmemfunc (t)
tree t;
{
if (TREE_CODE (t) == PTRMEM_CST)
{
tree delta;
tree pfn;
expand_ptrmemfunc_cst (t, &delta, &pfn);
if (pfn)
return pfn;
}
return build_component_ref (t, pfn_identifier, NULL_TREE, 0);
}
/* Expression EXPR is about to be implicitly converted to TYPE. Warn
if this is a potentially dangerous thing to do. Returns a possibly
marked EXPR. */
tree
dubious_conversion_warnings (type, expr, errtype, fndecl, parmnum)
tree type;
tree expr;
const char *errtype;
tree fndecl;
int parmnum;
{
if (TREE_CODE (type) == REFERENCE_TYPE)
type = TREE_TYPE (type);
/* Issue warnings about peculiar, but legal, uses of NULL. */
if (ARITHMETIC_TYPE_P (type) && expr == null_node)
{
if (fndecl)
warning ("passing NULL used for non-pointer %s %P of `%D'",
errtype, parmnum, fndecl);
else
warning ("%s to non-pointer type `%T' from NULL", errtype, type);
}
/* Warn about assigning a floating-point type to an integer type. */
if (TREE_CODE (TREE_TYPE (expr)) == REAL_TYPE
&& TREE_CODE (type) == INTEGER_TYPE)
{
if (fndecl)
warning ("passing `%T' for %s %P of `%D'",
TREE_TYPE (expr), errtype, parmnum, fndecl);
else
warning ("%s to `%T' from `%T'", errtype, type, TREE_TYPE (expr));
}
/* And warn about assigning a negative value to an unsigned
variable. */
else if (TREE_UNSIGNED (type) && TREE_CODE (type) != BOOLEAN_TYPE)
{
if (TREE_CODE (expr) == INTEGER_CST
&& TREE_NEGATED_INT (expr))
{
if (fndecl)
warning ("passing negative value `%E' for %s %P of `%D'",
expr, errtype, parmnum, fndecl);
else
warning ("%s of negative value `%E' to `%T'",
errtype, expr, type);
}
overflow_warning (expr);
if (TREE_CONSTANT (expr))
expr = fold (expr);
}
return expr;
}
/* Convert value RHS to type TYPE as preparation for an assignment to
an lvalue of type TYPE. ERRTYPE is a string to use in error
messages: "assignment", "return", etc. If FNDECL is non-NULL, we
are doing the conversion in order to pass the PARMNUMth argument of
FNDECL. */
static tree
convert_for_assignment (type, rhs, errtype, fndecl, parmnum)
tree type, rhs;
const char *errtype;
tree fndecl;
int parmnum;
{
register enum tree_code codel = TREE_CODE (type);
register tree rhstype;
register enum tree_code coder;
if (codel == OFFSET_TYPE)
my_friendly_abort (990505);
if (TREE_CODE (rhs) == OFFSET_REF)
rhs = resolve_offset_ref (rhs);
/* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
rhs = TREE_OPERAND (rhs, 0);
rhstype = TREE_TYPE (rhs);
coder = TREE_CODE (rhstype);
if (rhs == error_mark_node || rhstype == error_mark_node)
return error_mark_node;
if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
return error_mark_node;
rhs = dubious_conversion_warnings (type, rhs, errtype, fndecl, parmnum);
/* The RHS of an assignment cannot have void type. */
if (coder == VOID_TYPE)
{
error ("void value not ignored as it ought to be");
return error_mark_node;
}
/* Simplify the RHS if possible. */
if (TREE_CODE (rhs) == CONST_DECL)
rhs = DECL_INITIAL (rhs);
else if (coder != ARRAY_TYPE)
rhs = decl_constant_value (rhs);
/* [expr.ass]
The expression is implicitly converted (clause _conv_) to the
cv-unqualified type of the left operand.
We allow bad conversions here because by the time we get to this point
we are committed to doing the conversion. If we end up doing a bad
conversion, convert_like will complain. */
if (!can_convert_arg_bad (type, rhstype, rhs))
{
/* When -Wno-pmf-conversions is use, we just silently allow
conversions from pointers-to-members to plain pointers. If
the conversion doesn't work, cp_convert will complain. */
if (!warn_pmf2ptr
&& TYPE_PTR_P (type)
&& TYPE_PTRMEMFUNC_P (rhstype))
rhs = cp_convert (strip_top_quals (type), rhs);
else
{
/* If the right-hand side has unknown type, then it is an
overloaded function. Call instantiate_type to get error
messages. */
if (rhstype == unknown_type_node)
instantiate_type (type, rhs, itf_complain);
else if (fndecl)
error ("cannot convert `%T' to `%T' for argument `%P' to `%D'",
rhstype, type, parmnum, fndecl);
else
error ("cannot convert `%T' to `%T' in %s", rhstype, type,
errtype);
return error_mark_node;
}
}
return perform_implicit_conversion (strip_top_quals (type), rhs);
}
/* Convert RHS to be of type TYPE.
If EXP is non-zero, it is the target of the initialization.
ERRTYPE is a string to use in error messages.
Two major differences between the behavior of
`convert_for_assignment' and `convert_for_initialization'
are that references are bashed in the former, while
copied in the latter, and aggregates are assigned in
the former (operator=) while initialized in the
latter (X(X&)).
If using constructor make sure no conversion operator exists, if one does
exist, an ambiguity exists.
If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
tree
convert_for_initialization (exp, type, rhs, flags, errtype, fndecl, parmnum)
tree exp, type, rhs;
int flags;
const char *errtype;
tree fndecl;
int parmnum;
{
register enum tree_code codel = TREE_CODE (type);
register tree rhstype;
register enum tree_code coder;
/* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
if (TREE_CODE (rhs) == NOP_EXPR
&& TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
&& codel != REFERENCE_TYPE)
rhs = TREE_OPERAND (rhs, 0);
if (rhs == error_mark_node
|| (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
return error_mark_node;
if (TREE_CODE (rhs) == OFFSET_REF)
{
rhs = resolve_offset_ref (rhs);
if (rhs == error_mark_node)
return error_mark_node;
}
if (TREE_CODE (TREE_TYPE (rhs)) == REFERENCE_TYPE)
rhs = convert_from_reference (rhs);
if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
&& TREE_CODE (type) != ARRAY_TYPE
&& (TREE_CODE (type) != REFERENCE_TYPE
|| TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
|| (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
&& (TREE_CODE (type) != REFERENCE_TYPE
|| TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
|| TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
rhs = default_conversion (rhs);
rhstype = TREE_TYPE (rhs);
coder = TREE_CODE (rhstype);
if (coder == ERROR_MARK)
return error_mark_node;
/* We accept references to incomplete types, so we can
return here before checking if RHS is of complete type. */
if (codel == REFERENCE_TYPE)
{
/* This should eventually happen in convert_arguments. */
int savew = 0, savee = 0;
if (fndecl)
savew = warningcount, savee = errorcount;
rhs = initialize_reference (type, rhs);
if (fndecl)
{
if (warningcount > savew)
cp_warning_at ("in passing argument %P of `%+D'", parmnum, fndecl);
else if (errorcount > savee)
cp_error_at ("in passing argument %P of `%+D'", parmnum, fndecl);
}
return rhs;
}
if (exp != 0)
exp = require_complete_type (exp);
if (exp == error_mark_node)
return error_mark_node;
if (TREE_CODE (rhstype) == REFERENCE_TYPE)
rhstype = TREE_TYPE (rhstype);
type = complete_type (type);
if (IS_AGGR_TYPE (type))
return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
return convert_for_assignment (type, rhs, errtype, fndecl, parmnum);
}
/* Expand an ASM statement with operands, handling output operands
that are not variables or INDIRECT_REFS by transforming such
cases into cases that expand_asm_operands can handle.
Arguments are same as for expand_asm_operands.
We don't do default conversions on all inputs, because it can screw
up operands that are expected to be in memory. */
void
c_expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line)
tree string, outputs, inputs, clobbers;
int vol;
const char *filename;
int line;
{
int noutputs = list_length (outputs);
register int i;
/* o[I] is the place that output number I should be written. */
register tree *o = (tree *) alloca (noutputs * sizeof (tree));
register tree tail;
/* Record the contents of OUTPUTS before it is modified. */
for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
o[i] = TREE_VALUE (tail);
/* Generate the ASM_OPERANDS insn;
store into the TREE_VALUEs of OUTPUTS some trees for
where the values were actually stored. */
expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line);
/* Copy all the intermediate outputs into the specified outputs. */
for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
{
if (o[i] != TREE_VALUE (tail))
{
expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
const0_rtx, VOIDmode, EXPAND_NORMAL);
free_temp_slots ();
/* Restore the original value so that it's correct the next
time we expand this function. */
TREE_VALUE (tail) = o[i];
}
/* Detect modification of read-only values.
(Otherwise done by build_modify_expr.) */
else
{
tree type = TREE_TYPE (o[i]);
if (CP_TYPE_CONST_P (type)
|| (IS_AGGR_TYPE_CODE (TREE_CODE (type))
&& C_TYPE_FIELDS_READONLY (type)))
readonly_error (o[i], "modification by `asm'", 1);
}
}
/* Those MODIFY_EXPRs could do autoincrements. */
emit_queue ();
}
/* If RETVAL is the address of, or a reference to, a local variable or
temporary give an appropraite warning. */
static void
maybe_warn_about_returning_address_of_local (retval)
tree retval;
{
tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
tree whats_returned = retval;
for (;;)
{
if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
whats_returned = TREE_OPERAND (whats_returned, 1);
else if (TREE_CODE (whats_returned) == CONVERT_EXPR
|| TREE_CODE (whats_returned) == NON_LVALUE_EXPR
|| TREE_CODE (whats_returned) == NOP_EXPR)
whats_returned = TREE_OPERAND (whats_returned, 0);
else
break;
}
if (TREE_CODE (whats_returned) != ADDR_EXPR)
return;
whats_returned = TREE_OPERAND (whats_returned, 0);
if (TREE_CODE (valtype) == REFERENCE_TYPE)
{
if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
|| TREE_CODE (whats_returned) == TARGET_EXPR)
{
/* Get the target. */
whats_returned = TREE_OPERAND (whats_returned, 0);
warning ("returning reference to temporary");
return;
}
if (TREE_CODE (whats_returned) == VAR_DECL
&& DECL_NAME (whats_returned)
&& TEMP_NAME_P (DECL_NAME (whats_returned)))
{
warning ("reference to non-lvalue returned");
return;
}
}
if (TREE_CODE (whats_returned) == VAR_DECL
&& DECL_NAME (whats_returned)
&& DECL_FUNCTION_SCOPE_P (whats_returned)
&& !(TREE_STATIC (whats_returned)
|| TREE_PUBLIC (whats_returned)))
{
if (TREE_CODE (valtype) == REFERENCE_TYPE)
cp_warning_at ("reference to local variable `%D' returned",
whats_returned);
else
cp_warning_at ("address of local variable `%D' returned",
whats_returned);
return;
}
}
/* Check that returning RETVAL from the current function is legal.
Return an expression explicitly showing all conversions required to
change RETVAL into the function return type, and to assign it to
the DECL_RESULT for the function. */
tree
check_return_expr (retval)
tree retval;
{
tree result;
/* The type actually returned by the function, after any
promotions. */
tree valtype;
int fn_returns_value_p;
/* A `volatile' function is one that isn't supposed to return, ever.
(This is a G++ extension, used to get better code for functions
that call the `volatile' function.) */
if (TREE_THIS_VOLATILE (current_function_decl))
warning ("function declared `noreturn' has a `return' statement");
/* Check for various simple errors. */
if (DECL_DESTRUCTOR_P (current_function_decl))
{
if (retval)
error ("returning a value from a destructor");
return NULL_TREE;
}
else if (DECL_CONSTRUCTOR_P (current_function_decl))
{
if (in_function_try_handler)
/* If a return statement appears in a handler of the
function-try-block of a constructor, the program is ill-formed. */
error ("cannot return from a handler of a function-try-block of a constructor");
else if (retval)
/* You can't return a value from a constructor. */
error ("returning a value from a constructor");
return NULL_TREE;
}
/* When no explicit return-value is given in a function with a named
return value, the named return value is used. */
result = DECL_RESULT (current_function_decl);
valtype = TREE_TYPE (result);
my_friendly_assert (valtype != NULL_TREE, 19990924);
fn_returns_value_p = !VOID_TYPE_P (valtype);
if (!retval && DECL_NAME (result) && fn_returns_value_p)
retval = result;
/* Check for a return statement with no return value in a function
that's supposed to return a value. */
if (!retval && fn_returns_value_p)
{
pedwarn ("return-statement with no value, in function declared with a non-void return type");
/* Clear this, so finish_function won't say that we reach the
end of a non-void function (which we don't, we gave a
return!). */
current_function_returns_null = 0;
}
/* Check for a return statement with a value in a function that
isn't supposed to return a value. */
else if (retval && !fn_returns_value_p)
{
if (VOID_TYPE_P (TREE_TYPE (retval)))
/* You can return a `void' value from a function of `void'
type. In that case, we have to evaluate the expression for
its side-effects. */
finish_expr_stmt (retval);
else
pedwarn ("return-statement with a value, in function declared with a void return type");
current_function_returns_null = 1;
/* There's really no value to return, after all. */
return NULL_TREE;
}
else if (!retval)
/* Remember that this function can sometimes return without a
value. */
current_function_returns_null = 1;
else
/* Remember that this function did return a value. */
current_function_returns_value = 1;
/* Only operator new(...) throw(), can return NULL [expr.new/13]. */
if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
|| DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
&& !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
&& ! flag_check_new
&& null_ptr_cst_p (retval))
warning ("`operator new' must not return NULL unless it is declared `throw()' (or -fcheck-new is in effect)");
/* Effective C++ rule 15. See also start_function. */
if (warn_ecpp
&& DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR)
&& retval != current_class_ref)
warning ("`operator=' should return a reference to `*this'");
/* The fabled Named Return Value optimization, as per [class.copy]/15:
[...] For a function with a class return type, if the expression
in the return statement is the name of a local object, and the cv-
unqualified type of the local object is the same as the function
return type, an implementation is permitted to omit creating the tem-
porary object to hold the function return value [...]
So, if this is a value-returning function that always returns the same
local variable, remember it.
It might be nice to be more flexible, and choose the first suitable
variable even if the function sometimes returns something else, but
then we run the risk of clobbering the variable we chose if the other
returned expression uses the chosen variable somehow. And people expect
this restriction, anyway. (jason 2000-11-19)
See finish_function, genrtl_start_function, and declare_return_variable
for other pieces of this optimization. */
if (fn_returns_value_p && flag_elide_constructors)
{
if (retval != NULL_TREE
&& (current_function_return_value == NULL_TREE
|| current_function_return_value == retval)
&& TREE_CODE (retval) == VAR_DECL
&& DECL_CONTEXT (retval) == current_function_decl
&& ! TREE_STATIC (retval)
&& (DECL_ALIGN (retval)
>= DECL_ALIGN (DECL_RESULT (current_function_decl)))
&& same_type_p ((TYPE_MAIN_VARIANT
(TREE_TYPE (retval))),
(TYPE_MAIN_VARIANT
(TREE_TYPE (TREE_TYPE (current_function_decl))))))
current_function_return_value = retval;
else
current_function_return_value = error_mark_node;
}
/* We don't need to do any conversions when there's nothing being
returned. */
if (!retval || retval == error_mark_node)
return retval;
/* Do any required conversions. */
if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
/* No conversions are required. */
;
else
{
/* The type the function is declared to return. */
tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
/* First convert the value to the function's return type, then
to the type of return value's location to handle the
case that functype is smaller than the valtype. */
retval = convert_for_initialization
(NULL_TREE, functype, retval, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
"return", NULL_TREE, 0);
retval = convert (valtype, retval);
/* If the conversion failed, treat this just like `return;'. */
if (retval == error_mark_node)
return retval;
/* We can't initialize a register from a AGGR_INIT_EXPR. */
else if (! current_function_returns_struct
&& TREE_CODE (retval) == TARGET_EXPR
&& TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
retval = build (COMPOUND_EXPR, TREE_TYPE (retval), retval,
TREE_OPERAND (retval, 0));
else
maybe_warn_about_returning_address_of_local (retval);
}
/* Actually copy the value returned into the appropriate location. */
if (retval && retval != result)
retval = build (INIT_EXPR, TREE_TYPE (result), result, retval);
return retval;
}
/* Returns non-zero if the pointer-type FROM can be converted to the
pointer-type TO via a qualification conversion. If CONSTP is -1,
then we return non-zero if the pointers are similar, and the
cv-qualification signature of FROM is a proper subset of that of TO.
If CONSTP is positive, then all outer pointers have been
const-qualified. */
static int
comp_ptr_ttypes_real (to, from, constp)
tree to, from;
int constp;
{
int to_more_cv_qualified = 0;
for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
{
if (TREE_CODE (to) != TREE_CODE (from))
return 0;
if (TREE_CODE (from) == OFFSET_TYPE
&& same_type_p (TYPE_OFFSET_BASETYPE (from),
TYPE_OFFSET_BASETYPE (to)))
continue;
/* Const and volatile mean something different for function types,
so the usual checks are not appropriate. */
if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
{
if (!at_least_as_qualified_p (to, from))
return 0;
if (!at_least_as_qualified_p (from, to))
{
if (constp == 0)
return 0;
else
++to_more_cv_qualified;
}
if (constp > 0)
constp &= TYPE_READONLY (to);
}
if (TREE_CODE (to) != POINTER_TYPE)
return
same_type_ignoring_top_level_qualifiers_p (to, from)
&& (constp >= 0 || to_more_cv_qualified);
}
}
/* When comparing, say, char ** to char const **, this function takes the
'char *' and 'char const *'. Do not pass non-pointer types to this
function. */
int
comp_ptr_ttypes (to, from)
tree to, from;
{
return comp_ptr_ttypes_real (to, from, 1);
}
/* Returns 1 if to and from are (possibly multi-level) pointers to the same
type or inheritance-related types, regardless of cv-quals. */
int
ptr_reasonably_similar (to, from)
tree to, from;
{
for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
{
/* Any target type is similar enough to void. */
if (TREE_CODE (to) == VOID_TYPE
|| TREE_CODE (from) == VOID_TYPE)
return 1;
if (TREE_CODE (to) != TREE_CODE (from))
return 0;
if (TREE_CODE (from) == OFFSET_TYPE
&& comptypes (TYPE_OFFSET_BASETYPE (to),
TYPE_OFFSET_BASETYPE (from),
COMPARE_BASE | COMPARE_RELAXED))
continue;
if (TREE_CODE (to) == INTEGER_TYPE
&& TYPE_PRECISION (to) == TYPE_PRECISION (from))
return 1;
if (TREE_CODE (to) == FUNCTION_TYPE)
return 1;
if (TREE_CODE (to) != POINTER_TYPE)
return comptypes
(TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
COMPARE_BASE | COMPARE_RELAXED);
}
}
/* Like comp_ptr_ttypes, for const_cast. */
static int
comp_ptr_ttypes_const (to, from)
tree to, from;
{
for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
{
if (TREE_CODE (to) != TREE_CODE (from))
return 0;
if (TREE_CODE (from) == OFFSET_TYPE
&& same_type_p (TYPE_OFFSET_BASETYPE (from),
TYPE_OFFSET_BASETYPE (to)))
continue;
if (TREE_CODE (to) != POINTER_TYPE)
return same_type_ignoring_top_level_qualifiers_p (to, from);
}
}
/* Like comp_ptr_ttypes, for reinterpret_cast. */
static int
comp_ptr_ttypes_reinterpret (to, from)
tree to, from;
{
int constp = 1;
for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
{
if (TREE_CODE (from) == OFFSET_TYPE)
from = TREE_TYPE (from);
if (TREE_CODE (to) == OFFSET_TYPE)
to = TREE_TYPE (to);
/* Const and volatile mean something different for function types,
so the usual checks are not appropriate. */
if (TREE_CODE (from) != FUNCTION_TYPE && TREE_CODE (from) != METHOD_TYPE
&& TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
{
if (!at_least_as_qualified_p (to, from))
return 0;
if (! constp
&& !at_least_as_qualified_p (from, to))
return 0;
constp &= TYPE_READONLY (to);
}
if (TREE_CODE (from) != POINTER_TYPE
|| TREE_CODE (to) != POINTER_TYPE)
return 1;
}
}
/* Returns the type qualifiers for this type, including the qualifiers on the
elements for an array type. */
int
cp_type_quals (type)
tree type;
{
type = strip_array_types (type);
return TYPE_QUALS (type);
}
/* Returns non-zero if the TYPE contains a mutable member */
int
cp_has_mutable_p (type)
tree type;
{
type = strip_array_types (type);
return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
}
/* Subroutine of casts_away_constness. Make T1 and T2 point at
exemplar types such that casting T1 to T2 is casting away castness
if and only if there is no implicit conversion from T1 to T2. */
static void
casts_away_constness_r (t1, t2)
tree *t1;
tree *t2;
{
int quals1;
int quals2;
/* [expr.const.cast]
For multi-level pointer to members and multi-level mixed pointers
and pointers to members (conv.qual), the "member" aspect of a
pointer to member level is ignored when determining if a const
cv-qualifier has been cast away. */
if (TYPE_PTRMEM_P (*t1))
*t1 = build_pointer_type (TREE_TYPE (TREE_TYPE (*t1)));
if (TYPE_PTRMEM_P (*t2))
*t2 = build_pointer_type (TREE_TYPE (TREE_TYPE (*t2)));
/* [expr.const.cast]
For two pointer types:
X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
K is min(N,M)
casting from X1 to X2 casts away constness if, for a non-pointer
type T there does not exist an implicit conversion (clause
_conv_) from:
Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
to
Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
if (TREE_CODE (*t1) != POINTER_TYPE
|| TREE_CODE (*t2) != POINTER_TYPE)
{
*t1 = cp_build_qualified_type (void_type_node,
cp_type_quals (*t1));
*t2 = cp_build_qualified_type (void_type_node,
cp_type_quals (*t2));
return;
}
quals1 = cp_type_quals (*t1);
quals2 = cp_type_quals (*t2);
*t1 = TREE_TYPE (*t1);
*t2 = TREE_TYPE (*t2);
casts_away_constness_r (t1, t2);
*t1 = build_pointer_type (*t1);
*t2 = build_pointer_type (*t2);
*t1 = cp_build_qualified_type (*t1, quals1);
*t2 = cp_build_qualified_type (*t2, quals2);
}
/* Returns non-zero if casting from TYPE1 to TYPE2 casts away
constness. */
static int
casts_away_constness (t1, t2)
tree t1;
tree t2;
{
if (TREE_CODE (t2) == REFERENCE_TYPE)
{
/* [expr.const.cast]
Casting from an lvalue of type T1 to an lvalue of type T2
using a reference cast casts away constness if a cast from an
rvalue of type "pointer to T1" to the type "pointer to T2"
casts away constness. */
t1 = (TREE_CODE (t1) == REFERENCE_TYPE
? TREE_TYPE (t1) : t1);
return casts_away_constness (build_pointer_type (t1),
build_pointer_type (TREE_TYPE (t2)));
}
if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
/* [expr.const.cast]
Casting from an rvalue of type "pointer to data member of X
of type T1" to the type "pointer to data member of Y of type
T2" casts away constness if a cast from an rvalue of type
"pointer to T1" to the type "pointer to T2" casts away
constness. */
return casts_away_constness
(build_pointer_type (TREE_TYPE (TREE_TYPE (t1))),
build_pointer_type (TREE_TYPE (TREE_TYPE (t2))));
/* Casting away constness is only something that makes sense for
pointer or reference types. */
if (TREE_CODE (t1) != POINTER_TYPE
|| TREE_CODE (t2) != POINTER_TYPE)
return 0;
/* Top-level qualifiers don't matter. */
t1 = TYPE_MAIN_VARIANT (t1);
t2 = TYPE_MAIN_VARIANT (t2);
casts_away_constness_r (&t1, &t2);
if (!can_convert (t2, t1))
return 1;
return 0;
}
/* Returns TYPE with its cv qualifiers removed
TYPE is T cv* .. *cv where T is not a pointer type,
returns T * .. *. (If T is an array type, then the cv qualifiers
above are those of the array members.) */
static tree
strip_all_pointer_quals (type)
tree type;
{
if (TREE_CODE (type) == POINTER_TYPE)
return build_pointer_type (strip_all_pointer_quals (TREE_TYPE (type)));
else if (TREE_CODE (type) == OFFSET_TYPE)
return build_offset_type (TYPE_OFFSET_BASETYPE (type),
strip_all_pointer_quals (TREE_TYPE (type)));
else
return TYPE_MAIN_VARIANT (type);
}